Disease Severity and Perinatal Outcomes of Pregnant Patients With Coronavirus Disease 2019 (COVID-19)

Trimester and severity of SARS-CoV-2 infection during pregnancy and risk of hypertensive disorders in pregnancy

OBJECTIVE

SARS-CoV-2 infection during pregnancy has been linked with an increased risk of hypertensive disorders of pregnancy (HDP). The aim of this study was to examine how both trimester and severity of SARS-CoV-2 infection impact HDP.

METHODS

We conducted a cohort study of SARS-CoV-2-infected individuals during pregnancy (n = 205) and examined the association between trimester and severity of infection with incidence of HDP using modified Poisson regression models to calculate risk ratios (RR) and 95% confidence intervals (CI). We stratified the analysis of trimester by severity to understand the role of timing of infection among those with similar symptomatology and also examined timing of infection as a continuous variable.

RESULTS

Compared to a reference cohort from 2018, SARS-CoV-2 infection did not largely increase the risk of HDP (RR: 1.17; CI:0.90, 1.51), but a non-statistically significant higher risk of preeclampsia was observed (RR: 1.33; CI:0.89, 1.98), in our small sample. Among the SARS-CoV-2 cohort, severity was linked with risk of HDP, with infections requiring hospitalization increasing the risk of HDP compared to asymptomatic/mild infections. Trimester of infection was not associated with risk of HDP, but a slight decline in the risk of HDP was observed with later gestational week of infection. Among patients with asymptomatic or mild symptoms, SARS-CoV-2 in the first trimester conferred a higher risk of HDP compared to the third trimester (RR: 1.70; CI:0.77, 3.77), although estimates were imprecise.

CONCLUSION

SARS-CoV-2 infection in early pregnancy may increase the risk of HDP compared to infection later in pregnancy.

Prediction of COVID-19 Severity at Delivery after Asymptomatic or Mild COVID-19 during Pregnancy

OBJECTIVE

 This study aimed to develop a prediction model that estimates the probability that a pregnant person who has had asymptomatic or mild coronavirus disease 2019 (COVID-19) prior to delivery admission will progress in severity to moderate, severe, or critical COVID-19.

STUDY DESIGN

 This was a secondary analysis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive patients who delivered from March through December 2020 at hospitals across the United States. Those eligible for this analysis presented for delivery with a current or previous asymptomatic or mild SARS-CoV-2 infection. The primary outcome was moderate, severe, or critical COVID-19 during the delivery admission through 42 days postpartum. The prediction model was developed and internally validated using stratified cross-validation with stepwise backward elimination, incorporating only variables that were known on the day of hospital admission.

RESULTS

 Of the 2,818 patients included, 26 (0.9%; 95% confidence interval [CI], 0.6-1.3%) developed moderate-severe-critical COVID-19 during the study period. Variables in the prediction model were gestational age at delivery admission (adjusted odds ratio [aOR], 1.15; 95% CI, 1.08-1.22 per 1-week decrease), a hypertensive disorder in a prior pregnancy (aOR 3.05; 95% CI, 1.25-7.46), and systolic blood pressure at admission (aOR, 1.04; 95% CI, 1.02-1.05 per mm Hg increase). This model yielded an area under the receiver operating characteristic curve of 0.82 (95% CI, 0.72-0.91).

CONCLUSION

 Among individuals presenting for delivery who had asymptomatic-mild COVID-19, gestational age at delivery admission, a hypertensive disorder in a prior pregnancy, and systolic blood pressure at admission were predictive of delivering with moderate, severe, or critical COVID-19. This prediction model may be a useful tool to optimize resources for SARS-CoV-2-infected pregnant individuals admitted for delivery.

KEY POINTS

· Three factors were associated with delivery with more severe COVID-19.. · The developed model yielded an area under the receiver operating characteristic curve of 0.82 and model fit was good.. · The model may be useful tool for SARS-CoV-2 infected pregnancies admitted for delivery..

COVID-19 in pregnancy: prevalence, management, and outcomes in a single large health system

OBJECTIVE

This study assessed the prevalence of SARS-CoV-2 positivity in a cohort of pregnant patients served by a single health system. Treatments and outcomes are compared by maternal SARS-CoV-2 status and COVID-19 symptomatology.

METHODS

This was a retrospective cohort study of patients with delivery outcomes from March 2020-December 2021. SARS-CoV-2 positivity was defined by patients who had a positive test or COVID-19 diagnosis during pregnancy. Descriptive analysis compared demographics, medical management during pregnancy, and both perinatal and non-obstetric outcomes by SARS-CoV-2/COVID-19 status (negative, positive-asymptomatic, and positive-symptomatic).

RESULTS

Of 24,310 pregnancies, 94.6% were negative, 3.9% were positive-asymptomatic, and 1.5% were positive-symptomatic. Non-delivery hospitalizations were highest among positive-symptomatic patients (16.8%), followed by positive-asymptomatic patients (3.9%) and lastly negative patients (2.7%) (p < 0.001). Likewise, Intensive Care Unit (ICU) admissions during an antepartum or delivery admission were higher for positive-symptomatic patients (13.0%) compared to positive-asymptomatic patients or negative patients (0.7% and 0.5%, respectively, p < 0.001). The rate of preterm birth was significantly higher in positive-symptomatic patients compared to positive-asymptomatic and negative patients (15.7% vs. 9.5% and 9.8%, respectively, p = 0.002). There were no statistically significant differences in rates of miscarriage or intrauterine fetal demise. Maternal readmission, administration of corticosteroids for fetal lung maturity, birthweight, and neonatal intensive care unit (NICU) admission were significantly affected by SARS-CoV-2 status.

CONCLUSION

Pregnant patients testing positive for SARS-CoV-2 were mostly asymptomatic and identified during routine screening. Symptomatic patients were significantly more likely to require hospitalization and ICU admission with some increase in adverse perinatal outcomes.

COVID-19 is associated with early emergence of preeclampsia: results from a large regional collaborative

Objective: To investigate the relationship between preeclampsia and SARS-CoV-2 infection during pregnancy. Methods: This was a retrospective cohort study of pregnant women between March and October 2020. Pregnant patients admitted to 14 obstetrical centers in Michigan, USA formed the study population. Of the N = 1458 participants, 369 had SARS-CoV-2 infection (cases). Controls were uninfected pregnancies that were delivered in the same obstetric unit within 30 days of the index case. Robust Poisson regression was used to estimate relative risk (RR) of preterm and term preeclampsia and preeclampsia involving placental lesions. The analysis included adjustment for relevant clinical and demographic risk factors.Results: SARS-CoV-2 infection during pregnancy increased the risk of preeclampsia [adjusted aRR = 1.69 (1.26-2.26)], preeclampsia involving placental lesions [aRR = 1.97(1.14-3.4)] and preterm preeclampsia 2.48(1.48-4.17). Although the highest rate of preeclampsia was observed in patients infected with SARS-CoV-2 who were symptomatic (18.4%), there was increased risk even in asymptomatic SARS-CoV-2 infected patients (14.2%) relative to non-infected controls (8.7%) (p < 0.05). This association with symptomatology was also noted with preterm preeclampsia for which the rate doubled from 2.7% in controls to 5.2% in asymptomatic cases and reached 11.8% among symptomatic cases (p < 0.05). The rate of preterm preeclampsia among cases of pregnant people self-identified as Black reached 10.1% and was almost double the rate of the reminder of the group of infected pregnancies (5.3%), although the rate among uninfected was almost the same (2.7%) for both Black and non-Black groups (interaction p = 0.05).Conclusions: Infection with SARS-CoV-2 increases the risk of preeclampsia even in the absence of symptoms, although symptomatic persons are at even higher risk. Racial disparities in the development of preterm preeclampsia after SARS-CoV-2 infection may explain discrepancies in prematurity between different populations.

Clinical characteristics of pregnant women with COVID-19 and infection outcomes in one of the largest cities in the Brazilian Amazon

BACKGROUND

Pregnancy can be a risk factor for the development of more severe COVID-19 with a possible increase in the risk of complications during pregnancy/birth and adverse neonatal outcomes. This study aimed to describe and analyze the clinical and epidemiological aspects of SARS-CoV-2 infection in women in the perinatal period attended in the city of Belém, northern region of Brazil.

METHODS

This is a clinical, observational, analytical, and cross-sectional study with a quantitative approach, conducted at the Santa Casa de Misericórdia do Pará Foundation (FSCMPA). It included 230 pregnant women hospitalized at FSCMPA with a positive SARS-CoV-2 RT-PCR molecular test between April 2020 and June 2022. Clinical and epidemiological information (origin, gestational age, prenatal care, comorbidities, birth complications, and chest tomography) were obtained from medical records, and correlation was made between the types of cases (mild, moderate, and severe) and maternal outcome. The chi-square test and G test were used to assess the possibility of association between variables.

RESULTS

Evidence of association was observed between the severity of COVID-19 and the following parameters: gestational age, specific pregnancy comorbidities, baby and maternal death, birth complications, and prematurity. Dyspnea, headache, anosmia, odynophagia, diarrhea, and chest pain were the symptoms most related to disease aggravation. The maternal mortality rate in the study was 8.7%.

CONCLUSION

Specific pregnancy-related and pre-existing comorbidities associated with SARS-CoV-2 infection directly contribute to the worsening clinical condition, leading to complications such as prematurity, fetal, and maternal death.

Assessing the safety and pharmacokinetics of casirivimab and imdevimab (CAS+IMD) in a cohort of pregnant outpatients with COVID-19: results from an adaptive, multicentre, randomised, double-blind, phase 1/2/3 study

OBJECTIVE

Pregnant women with COVID-19 are at elevated risk for severe outcomes, but clinical data on management of these patients are limited. Monoclonal antibodies, such as casirivimab plus imdevimab (CAS+IMD), have proven effective in treating non-pregnant adults with COVID-19, prompting further evaluation in pregnant women.

METHODS

A phase 3 portion of an adaptive, multicentre, randomised, double-blind, placebo-controlled trial evaluated the safety, clinical outcomes, pharmacokinetics and immunogenicity of CAS+IMD (1200 mg or 2400 mg) in the treatment of pregnant outpatients with COVID-19 (NCT04425629). Participants were enrolled between December 2020 and November 2021, prior to the emergence of Omicron-lineage variants against which CAS+IMD is not active. Safety was evaluated in randomised participants who received study drug (n=80); clinical outcomes were evaluated in all randomised participants (n=82). Only two pregnant participants received placebo, limiting conclusions regarding treatment effect. Infants born to pregnant participants were followed for developmental outcomes ≤1 year of age.

RESULTS

In pregnant participants, CAS+IMD was well tolerated, with no grade ≥2 hypersensitivity or infusion-related reactions reported. There were no participant deaths, and only one COVID-19-related medically attended visit. Although two pregnancies (3%) reported issues in the fetus/neonate, they were confounded by maternal history or considered to be due to an alternate aetiology. No adverse developmental outcomes in infants ≤1 year of age were considered related to in utero exposure to the study drug. CAS+IMD 1200 mg and 2400 mg rapidly and similarly reduced viral loads, with a dose-proportional increase in concentrations of CAS+IMD in serum. Pharmacokinetics were consistent with that reported in the general population. Immunogenicity incidence was low.

CONCLUSION

CAS+IMD treatment of pregnant outpatients with COVID-19 showed similar safety, clinical outcomes and pharmacokinetic profiles to that observed in non-pregnant adults. There was no evidence of an impact on developmental outcomes in infants ≤1 year of age.

TRIAL REGISTRATION NUMBER

NCT04425629.

Association of maternal infection of SARS-CoV-2 and neonatal susceptibility: A retrospective cohort study

Objective

This study aims to assess the risk of neonatal susceptibility to COVID-19 among pregnant women.

Methods

We conducted a retrospective cohort study involving 1089 pregnant women ≥28 weeks of gestational age, who were categorized into infected and uninfected groups. Data for all participants were collected through a comprehensive review of electronic medical records and follow-up phone calls. The primary outcome was neonatal infection with SARS-CoV-2, while secondary outcomes included delivery patterns and gestational age at delivery.

Results

Maternal vaccination (OR 95%CI:0.63[0.46, 0.85]) and maternal infection with SARS-CoV-2 (OR 95%CI: 0.45[0.34, 0.60]) were found to be associated with a decreased risk of neonatal infection. The infected group exhibited a lower neonatal SARS-CoV-2 infection rate (25.93%) compared to the uninfected group (45.15%). Logistic regression analysis identified several risk factors associated with an increased risk of neonatal infection, including pregnancy BMI (OR 95%CI: 1.04[1.01, 1.08]), age at first pregnancy (OR 95%CI: 1.05[1.01, 1.10]), age at menarche (OR 95%CI: 1.13[1.02, 1.26]), and parturition (Yes vs. No) (OR 95%CI:1.4 [1.04,1.88]).

Conclusion

Maternal vaccination and perinatal infection with SARS-CoV-2 play a protective role in preventing neonatal SARS-CoV-2 infection.

Neonatal SARS-CoV-2 mRNA Vaccination Efficacy Is Influenced by Maternal Antibodies

PROBLEM

Vaccination in pregnancy guards against infection. Maternal antibodies, however, can inhibit antibody production in neonates. We sought to determine the effects of maternal vaccination on neonatal immune response to a SARS-CoV-2 mRNA vaccine.

METHOD OF STUDY

We hypothesized that mRNA-lipid nanoparticles (LNP) vaccination allows for a de novo neonatal antibody response even in the presence of vertically transmitted maternal antibodies. Female mice were vaccinated with SARS-CoV-2 spike receptor binding domain (RBD) mRNA-LNPs. Mice were then bred, and 21-day-old pups were inoculated with the same mRNA-LNPs. Spike-specific IgG ELISAs were performed using mouse serum. A SARS-CoV-2 spike protein peptide library to perform peptide ELISAs characterized high affinity binding domains within the spike protein. Results were analyzed with one-way ANOVAs with Tukey's multiple comparisons tests.

RESULTS

Compared to pups of unvaccinated dams, there were high levels of spike-specific IgG detected in the pups of vaccinated dams at 3 weeks of life (p < 0.0001). After neonatal vaccination, pups of unvaccinated dams had higher spike-specific serum IgG than pups of vaccinated dams at 12 weeks of life (p < 0.001). Antibody specificity to peptide moieties within spike RBD were similar when comparing a vaccinated dam to her pup at Week 3 of life, with different binding affinities observed in the pups by Week 15 of life.

CONCLUSIONS

Pre-existing maternal antibodies may partially blunt the initial neonatal antibody response to mRNA-LNPs vaccination. This vaccine strategy, however, does not prohibit the subsequent development of a broad range of RBD antibody specificities that may be protective.

Serological Outcome in the First Months of Life of Children Born to Mothers with SARS-CoV-2 Infection during Pregnancy

BACKGROUND

The objective of this study is to analyze the transplacental transmission of SARS-CoV-2 antibodies, their persistence in newborns, the factors that may influence this transmission, and the protection these antibodies confer over time.

METHODS

This prospective cohort was conducted in a tertiary pediatric hospital in the Barcelona Metropolitan Region, Spain. It included neonates born to mothers who had SARS-CoV-2 infection during pregnancy or delivery between August 2020 and January 2022. We followed the recruited children for at least six months, and blood tests were performed to determine the presence of SARS-CoV-2 antibodies.

RESULTS

A total of 101 children were recruited. Among the serologies performed on children under three months of age, 44/82 were positive (53.7%). Newborns whose mothers presented more severe disease exhibited higher seropositivity odds (coefficient 9.747; p = 0.002). There were increased preterm deliveries when maternal infection occurred closer to the time of delivery. No severe SARS-CoV-2 infections were detected in children during the follow-up.

CONCLUSIONS

Slightly more than half of the SARS-CoV-2 serologies performed in the first three months were positive. This appears to confer protection during early childhood. The severity of maternal infection is the most significant factor influencing the transmission of antibodies in children born to unvaccinated mothers.

Rural-urban and racial differences in cesarean deliveries before and during the COVID-19 pandemic in South Carolina

PROBLEM

Unnecessary cesarean delivery increases the risk of complications for birthing people and infants.

BACKGROUND

Examining the intersectionality of rural and racial disparities in low-risk cesarean delivery is necessary to improve equity in quality obstetrics care.

AIM

To evaluate rural and racial/ethnic differences in Nulliparous, Term, Singleton, Vertex (NTSV) and primary cesarean delivery rates before and during the COVID-19 pandemic in South Carolina.

METHODS

This retrospective cohort study used birth certificates linked to all-payer hospital discharge data for South Carolina childbirths from 2018 to 2021. Multilevel logistic regressions examined differences in cesarean outcomes by rural/urban hospital location and race/ethnicity of birthing people during pre-pandemic (January 2018-February 2020) and peri-pandemic periods (March 2020-December 2021), adjusting for maternal, infant, and hospital characteristics among two low-risk pregnancy cohorts: 1) Nulliparous, Term, Singleton, Vertex (NTSV, n = 65,974) and 2) those without prior cesarean (primary, n = 167,928).

FINDINGS

Black vs. White disparities remained for NTSV cesarean in adjusted models (urban pre-pandemic aOR = 1.34, 95 %CI 1.23-1.46) but were not significantly different for primary cesarean, apart from rural settings peri-pandemic (aOR = 0.87, 95 %CI 0.79-0.96). Hispanic individuals had higher adjusted odds of NTSV cesarean only for rural settings pre-pandemic (aOR = 1.28, 95 %CI 1.05-1.56), but this disparity was not significant during the pandemic (aOR = 1.13, 95 %CI 0.93-1.37).

DISCUSSION AND CONCLUSION

Observed rural and racial/ethnic disparities in cesarean delivery outcomes were present before and during the COVID-19 pandemic. Strategies effective in reducing racial disparities in primary cesarean may be useful in also reducing Black vs. White NTSV cesarean disparities.

Post-Acute Sequelae of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) After Infection During Pregnancy

OBJECTIVE

To estimate the prevalence of post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (PASC) after infection with SARS-CoV-2 during pregnancy and to characterize associated risk factors.

METHODS

In a multicenter cohort study (NIH RECOVER [Researching COVID to Enhance Recovery]-Pregnancy Cohort), individuals who were pregnant during their first SARS-CoV-2 infection were enrolled across the United States from December 2021 to September 2023, either within 30 days of their infection or at differential time points thereafter. The primary outcome was PASC , defined as score of 12 or higher based on symptoms and severity as previously published by the NIH RECOVER-Adult Cohort, at the first study visit at least 6 months after the participant's first SARS-CoV-2 infection. Risk factors for PASC were evaluated, including sociodemographic characteristics, clinical characteristics before SARS-CoV-2 infection (baseline comorbidities, trimester of infection, vaccination status), and acute infection severity (classified by need for oxygen therapy). Multivariable logistic regression models were fitted to estimate associations between these characteristics and presence of PASC.

RESULTS

Of the 1,502 participants, 61.1% had their first SARS-CoV-2 infection on or after December 1, 2021 (ie, during Omicron variant dominance); 51.4% were fully vaccinated before infection; and 182 (12.1%) were enrolled within 30 days of their acute infection. The prevalence of PASC was 9.3% (95% CI, 7.9-10.9%) measured at a median of 10.3 months (interquartile range 6.1-21.5) after first infection. The most common symptoms among individuals with PASC were postexertional malaise (77.7%), fatigue (76.3%), and gastrointestinal symptoms (61.2%). In a multivariable model, the proportion PASC positive with vs without history of obesity (14.9% vs 7.5%, adjusted odds ratio [aOR] 1.65, 95% CI, 1.12-2.43), depression or anxiety disorder (14.4% vs 6.1%, aOR 2.64, 95% CI, 1.79-3.88) before first infection, economic hardship (self-reported difficulty covering expenses) (12.5% vs 6.9%, aOR 1.57, 95% CI, 1.05-2.34), and treatment with oxygen during acute SARS-CoV-2 infection (18.1% vs 8.7%, aOR 1.86, 95% CI, 1.00-3.44) were associated with increased prevalence of PASC.

CONCLUSION

The prevalence of PASC at a median time of 10.3 months after SARS-CoV-2 infection during pregnancy was 9.3% in the NIH RECOVER-Pregnancy Cohort. The predominant symptoms were postexertional malaise, fatigue, and gastrointestinal symptoms. Several socioeconomic and clinical characteristics were associated with PASC after infection during pregnancy.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , NCT05172024.

Maternal Immunizations: Past, Present, and Future

Maternal vaccines during pregnancy offer crucial protection against infections for both the pregnant person and their newborn. Vaccines against influenza, pertussis, coronavirus disease 2019, and respiratory syncytial virus are routinely recommended by the Centers for Disease Control and Prevention to safeguard pregnant women and their infants from potentially severe complications. Administering these vaccines during pregnancy helps transfer protective antibodies from the mother to the baby, enhancing immunity during the vulnerable early months of life. Extensive research supports the safety and efficacy of maternal vaccines, with numerous studies demonstrating their protective benefits for both pregnant people and newborns.

Retrospective Analysis of the Impact of SARS-CoV-2 (COVID-19) on Pregnancy and Neonatal Outcomes

Background: The novel coronavirus disease 2019 (COVID-19) was more devastating in people with comorbidities such as advanced age and immunodeficiency. Another group affected by COVID-19 was pregnant women. Immunological changes during pregnancy and conditions such as gestational diabetes and pre-eclampsia that occur during pregnancy also have effects on the fetus. The aim of this study was to analyze the effects of PCR-proven COVID-19 infection during pregnancy on fetus and newborn. Methods: Between December 2019 and October 2021, data from pregnant women with COVID-19 symptoms or a history of contact with people with COVID-19, infected with PCR-proven COVID-19 virus, were analyzed retrospectively. Clinical and laboratory data of pregnant women were analyzed. Death data associated with COVID-19 were evaluated. Clinical and laboratory findings of newborns related to COVID-19 and mortality data related to COVID-19 were recorded. The study received approval from the Gazi Yasargil Training and Research Hospital ethics committee (09.07.2021/853). Results: We evaluated 327 pregnant women who were followed up in our hospital and whose deliveries ended in live birth, stillbirth, miscarriage, or curettage. One hundred eighty-five (56.6%) of the pregnant women had at least one COVID-19-related symptom. We evaluated the data of 306 live births, 21 intrauterine fetal deaths, and 13 postnatal deaths. Among the postnatal deaths, five infants succumbed directly due to COVID-19 infection. A total of 23 live-born babies (7.5%) were classified as small for gestational age (SGA), while 80 babies (26.1%) were born before 37 weeks of gestation, and 32 babies (10.4%) were born before 32 weeks. Cord blood gas analysis revealed that 19 infants (6.3%) had pH < 7 and base excess (BE) < -12. The rate of perinatal asphyxia was significantly higher in babies born to mothers who did not survive (p = 0.027). A considerable number of infants, 119 (40.3%), were admitted to the neonatal intensive care unit (NICU). Among the seven infants with positive PCR results admitted to the NICU, five (4.2%) did not survive. Conclusion: While COVID-19 infection in pregnancy seriously affects mortality and morbidity in pregnant women, it also causes mortality and morbidity on the fetus.

Perinatal outcomes among pregnant patients with peripartum coronavirus disease 2019 infection

PURPOSE

Evaluate maternal and neonatal outcomes in peripartum coronavirus disease 2019 (COVID-19) positive women.

METHODS

A retrospective cohort study was conducted, comparing outcomes between women with and without peripartum COVID-19. All singleton deliveries from June 2020 to January 2022 were included. Univariate analysis was followed by multivariate analysis.

RESULTS

Of 26,827 singleton deliveries, 563 women had peripartum COVID-19, associated with preterm deliveries both near-term and remote from term [adjusted odds ratio (aOR) 1.6 and 2.0, respectively, p = 0.007 and 0.003]. Women with peripartum COVID-19 had a significantly higher rate of disseminated intravascular coagulation (DIC) (aOR 23.0, p < 0.001). Conversely, peripartum COVID-19 peripartum COVID-19 was negatively associated with premature rupture of membranes and prolonged maternal length of stay (aOR 0.7 and 0.5, respectively, p = 0.006 and <0.001). In cesarean delivery (CDs), patients with COVID-19 had higher rate of urgent CDs (75.5 vs. 56.1%, p < 0.001), higher rate of regional anesthesia (74.5 vs. 64.9%, p = 0.049), and longer anesthesia duration (86.1 vs. 53.4 min, p < 0.001). CD rate due to non-reassuring fetal heart rate (NRFHR) was significantly higher in women with COVID-19 (29.6 vs. 17.4%, p = 0.002). Conversely, CDs rate due to history of previous single CD was significantly higher in patients without COVID-19 diagnosis (13.6 vs. 4.1%, p = 0.006). Concerning neonatal outcomes, an association has been observed between COVID-19 and low one-minute APGAR score <5, as well as neonatal COVID-19 infection (aOR 61.8 and 1.7 respectively, p < 0.001 and p = 0.037).

CONCLUSIONS

Peripartum COVID-19 is associated with preterm deliveries, urgent CDs and DIC, potentially aligning with the infection's pathophysiology and coagulation alterations.

Pregnancy-related and Neonatal Outcomes during Omicron Variant-Dominant COVID-19 Pandemic among the Black-Dominant Population

OBJECTIVE

 This study aimed to determine the effect of the Omicron variant on pregnancy-related and neonatal outcomes among the Black-dominant population.

STUDY DESIGN

 We performed a single-center, retrospective cohort study during the prepandemic period from December 1, 2019, to February 29, 2020, and the Omicron surging period from December 1, 2021, to February 28, 2022. A total of 518 pregnant women were admitted for delivery during the study period. Multiple gestations (n = 21) and deliveries at less than 20 weeks of gestation (n = 5) were excluded. We analyzed and compared the sociodemographic and clinical data from mothers and their neonates between the two cohorts as well as between severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) positive and negative mothers during the Omicron surge. Subgroup analyses were also conducted specifically among the Black-only population.

RESULTS

 The cohorts were predominantly Black (88.6%), with smaller proportions of Hispanic (8.9%), Asian (0.8%), White (0.8%), and other ethnicities (0.8%). Of 492 singleton deliveries, 275 live births, 8 (2.8%) stillbirths, and 31 (11.3%) preterm births (PTBs) occurred during the prepandemic period, and 207 live births, 2 (1%) stillbirths, and 33 (15.9%) PTBs occurred during the Omicron wave. There was no statistically significant difference in the rates of PTBs, stillbirths, medically indicated PTBs, and cesarean delivery between the two cohorts. SARS-CoV-2-positive mothers were not at an increased risk of adverse outcomes. However, neonatal intensive care unit (NICU) admission rate significantly increased among neonates born to SARS-CoV-2 positive mothers compared with negative mothers (32.3 vs. 16.5%, p = 0.038). In subgroup analyses among Black individuals, this difference was not observed.

CONCLUSION

 There was no significant difference in pregnancy-related or neonatal outcomes in the Black-dominant population between the two cohorts. SARS-CoV-2 infection did not alter these findings except for an increased NICU admission rate among neonates born to SARS-CoV-2-positive mothers.

KEY POINTS

· Most pregnant women infected with SARS-CoV-2 during the Omicron wave were asymptomatic.. · The Omicron wave did not increase the risk of pregnancy-related or neonatal adverse outcomes when compared with the prepandemic period.. · Maternal SARS-CoV-2 infection increased NICU admission rate.. · Among Black individuals, no significant increase in adverse outcomes was observed during the Omicron pandemic..

Association Between Influenza Vaccination and SARS-CoV-2 Infection

BACKGROUND

Recent data in nonpregnant individuals suggest a protective effect of influenza vaccination against SARS-CoV-2 infection and its severity.

OBJECTIVES

Our primary objective was to evaluate whether influenza vaccination was associated with COVID-19 severity and pregnancy and neonatal outcomes among those infected with SARS-CoV-2. The secondary objective was to examine the association between influenza vaccination and SARS-CoV-2 infection.

STUDY DESIGN

Secondary analysis of a multicenter retrospective cohort of pregnant people who tested positive for SARS-CoV-2 between March and August 2020, and a cohort of random deliveries during the same time period. The associations between 2019 influenza vaccination and the primary outcome of moderate-to-critical COVID-19 as well as maternal and perinatal outcomes were examined among all people who tested positive for SARS-CoV-2 between March and August 2020. The association between 2019 influenza vaccination and having a positive SARS-CoV-2 test was examined among a cohort of individuals who delivered on randomly selected dates between March and August 2020. Univariable and multivariable analyses were performed.

RESULTS

Of 2325 people who tested positive for SARS-CoV-2, 1068 (45.9%) were vaccinated against influenza in 2019. Those who received the influenza vaccine were older, leaner, more likely to have private insurance, and identify as White or Hispanic. They were less likely to smoke tobacco and identify as Black. Overall, 419 (18.0%) had moderate, 193 (8.3%) severe, and 52 (2.2%) critical COVID-19. There was no association between influenza vaccination and moderate-to-critical COVID-19 (29.2% vs. 28.0%, adjusted OR 1.10, 95% CI 0.90-1.34) or adverse maternal and perinatal outcomes among those who tested positive. Of 8152 people who delivered in 2020, 4658 (57.1%) received the influenza vaccine. Prior vaccination was not associated with a difference in the odds of SARS-CoV-2 infection (3.8% vs. 4.2%, adjusted OR 0.94, 95% CI 0.74-1.19).

CONCLUSION

Prior influenza vaccination was not associated with decreased severity of COVID-19 or lower odds of SARS-CoV-2 infection in pregnancy.

Adverse delivery hospitalisation outcomes in 2020 during the COVID-19 pandemic

OBJECTIVE

To evaluate risk for adverse obstetric outcomes associated with the coronavirus disease 2019 (COVID-19) pandemic period and with COVID-19 diagnoses.

DESIGN

Serial cross-sectional study.

SETTING

A national sample of US delivery hospitalisations before (1/2016 to 2/2020) and during the first 10 months of (3/2020 to 12/2020) the COVID-19 pandemic.

POPULATION

All 2016-2020 US delivery hospitalisations in the National Inpatient Sample.

METHODS

Delivery hospitalisations were identified and stratified into pre-pandemic and pandemic periods and the likelihood of adverse obstetric outcomes was compared using logistic regression models with adjusted odds ratios (aOR) with 95% confidence intervals (CI) as measures of association. Risk for adverse outcomes was also analysed specifically for 2020 deliveries with a COVID-19 diagnosis.

MAIN OUTCOME MEASURE

Adverse maternal outcomes including respiratory complications and cardiac morbidity.

RESULTS

Of an estimated 18.2 million deliveries, 2.9 million occurred during the pandemic. The proportion of delivery hospitalisations with a COVID-19 diagnosis increased from 0.1% in March 2020 to 3.1% in December. Comparing the pandemic period to the pre-pandemic period, there were higher adjusted odds of transfusion (aOR 1.12, 95% CI 1.05-1.19), a respiratory complication composite (aOR 1.37, 95% CI 1.29-1.46), cardiac severe maternal morbidity (aOR 1.30, 95% 1.20-1.39), postpartum haemorrhage (aOR 1.19, 95% CI 1.15-1.24), placental abruption/antepartum haemorrhage (OR 1.04, 95% CI 1.00-1.08), and hypertensive disorders of pregnancy (OR 1.23, 95% CI 1.21-1.26). These associations were similar to unadjusted analysis. Risk for these outcomes during the pandemic period was significantly higher in the presence of a COVID-19 diagnosis.

CONCLUSIONS

In a national estimate of delivery hospitalisations, the odds of cardiac and respiratory outcomes were higher in 2020 compared with 2016-2019. COVID-19 diagnoses were specifically associated with a range of serious complications.

Association between acquiring SARS-CoV-2 during pregnancy and post-acute sequelae of SARS-CoV-2 infection: RECOVER electronic health record cohort analysis

Background

Little is known about post-acute sequelae of SARS-CoV-2 infection (PASC) after acquiring SARS-CoV-2 infection during pregnancy. We aimed to evaluate the association between acquiring SARS-CoV-2 during pregnancy compared with acquiring SARS-CoV-2 outside of pregnancy and the development of PASC.

Methods

This retrospective cohort study from the Researching COVID to Enhance Recovery (RECOVER) Initiative Patient-Centred Clinical Research Network (PCORnet) used electronic health record (EHR) data from 19 U.S. health systems. Females aged 18-49 years with lab-confirmed SARS-CoV-2 infection from March 2020 through June 2022 were included. Validated algorithms were used to identify pregnancies with a delivery at >20 weeks' gestation. The primary outcome was PASC, as previously defined by computable phenotype in the adult non-pregnant PCORnet EHR dataset, identified 30-180 days post-SARS-CoV-2 infection. Secondary outcomes were the 24 component diagnoses contributing to the PASC phenotype definition. Univariable comparisons were made for baseline characteristics between individuals with SARS-CoV-2 infection acquired during pregnancy compared with outside of pregnancy. Using inverse probability of treatment weighting to adjust for baseline differences, the association between SARS-CoV-2 infection acquired during pregnancy and the selected outcomes was modelled. The incident risk is reported as the adjusted hazard ratio (aHR) with 95% confidence intervals.

Findings

In total, 83,915 females with SARS-CoV-2 infection acquired outside of pregnancy and 5397 females with SARS-CoV-2 infection acquired during pregnancy were included in analysis. Non-pregnant females with SARS-CoV-2 infection were more likely to be older and have comorbid health conditions. SARS-CoV-2 infection acquired in pregnancy as compared with acquired outside of pregnancy was associated with a lower incidence of PASC (25.5% vs 33.9%; aHR 0.85, 95% CI 0.80-0.91). SARS-CoV-2 infection acquired in pregnant females was associated with increased risk for some PASC component diagnoses including abnormal heartbeat (aHR 1.67, 95% CI 1.43-1.94), abdominal pain (aHR 1.34, 95% CI 1.16-1.55), and thromboembolism (aHR 1.88, 95% CI 1.17-3.04), but decreased risk for other diagnoses including malaise (aHR 0.35, 95% CI 0.27-0.47), pharyngitis (aHR 0.36, 95% CI 0.26-0.48) and cognitive problems (aHR 0.39, 95% CI 0.27-0.56).

Interpretation

SARS-CoV-2 infection acquired during pregnancy was associated with lower risk of development of PASC at 30-180 days after incident SARS-CoV-2 infection in this nationally representative sample. These findings may be used to counsel pregnant and pregnant capable individuals, and direct future prospective study.

Funding

National Institutes of Health (NIH) Other Transaction Agreement (OTA) OT2HL16184.

Postpartum pharmacologic thromboprophylaxis and complications in a US cohort

BACKGROUND

Venous thromboembolism accounts for approximately 9% of pregnancy-related deaths in the United States. National guidelines recommend postpartum risk stratification and pharmacologic prophylaxis in at-risk individuals. Knowledge on modern rates of postpartum pharmacologic thromboprophylaxis and its associated risks is limited.

OBJECTIVE

This study aimed to describe the rate of, and factors associated with, initiation of postpartum pharmacologic prophylaxis for venous thromboembolism, and to assess associated adverse outcomes.

STUDY DESIGN

This was a secondary analysis of a multicenter cohort of individuals delivering on randomly selected days at 17 US hospitals (2019-2020). Medical records were reviewed by trained and certified personnel. Those with an antepartum diagnosis of venous thromboembolism, receiving antepartum anticoagulation, or known SARS-CoV-2 infection were excluded. The primary outcome was use of postpartum pharmacologic thromboprophylaxis. Secondary outcomes included bleeding complications, surgical site infection, hospital readmission, and venous thromboembolism through 6 weeks postpartum. The rate of thromboprophylaxis administration was assessed by mode of delivery, institution, and continuance to the outpatient setting. Multivariable regression models were developed using k-fold cross-validation with stepwise backward elimination to evaluate factors associated with thromboprophylaxis administration. Univariable and multivariable logistic models with propensity score covariate adjustment were performed to assess the association between thromboprophylaxis administration and adverse outcomes.

RESULTS

Of 21,114 individuals in the analytical cohort, 11.9% (95% confidence interval, 11.4%-12.3%) received postpartum pharmacologic thromboprophylaxis; the frequency of receipt was 29.8% (95% confidence interval, 28.7%-30.9%) following cesarean and 3.5% (95% confidence interval, 3.2%-3.8%) following vaginal delivery. Institutional rates of prophylaxis varied from 0.21% to 34.8%. Most individuals (83.3%) received thromboprophylaxis only as inpatients. In adjusted analysis, cesarean delivery (adjusted odds ratio, 19.17; 95% confidence interval, 16.70-22.00), hysterectomy (adjusted odds ratio, 15.70; 95% confidence interval, 4.35-56.65), and obesity (adjusted odds ratio, 3.45; 95% confidence interval, 3.02-3.95) were the strongest factors associated with thromboprophylaxis administration. Thromboprophylaxis administration was not associated with surgical site infection (0.9% vs 0.6%; odds ratio, 1.48; 95% confidence interval, 0.80-2.74), bleeding complications (0.2% vs 0.1%; odds ratio, 2.60; 95% confidence interval, 0.99-6.80), or postpartum readmission (0.9% vs 0.3%; adjusted odds ratio, 1.38; 95% confidence interval, 0.68-2.81). The overall rate of venous thromboembolism was 0.06% (95% confidence interval, 0.03%-0.10%) and was higher in those receiving prophylaxis (0.2%) compared with those not receiving prophylaxis (0.04%).

CONCLUSION

Approximately 1 in 10 patients received postpartum pharmacologic thromboprophylaxis in this US cohort. Rates of prophylaxis varied widely by institution. Cesarean delivery, hysterectomy, and obesity were predominant factors associated with postpartum thromboprophylaxis administration.

Pathogenesis of viral infections during pregnancy

SUMMARYViral infections during pregnancy are associated with significant adverse perinatal and fetal outcomes. Pregnancy is a unique immunologic and physiologic state, which can influence control of virus replication, severity of disease, and vertical transmission. The placenta is the organ of the maternal-fetal interface and provides defense against microbial infection while supporting the semi-allogeneic fetus via tolerogenic immune responses. Some viruses, such as cytomegalovirus, Zika virus, and rubella virus, can breach these defenses, directly infecting the fetus and having long-lasting consequences. Even without direct placental infection, other viruses, including respiratory viruses like influenza viruses and severe acute respiratory syndrome coronavirus 2, still cause placental damage and inflammation. Concentrations of progesterone and estrogens rise during pregnancy and contribute to immunological adaptations, placentation, and placental development and play a pivotal role in creating a tolerogenic environment at the maternal-fetal interface. Animal models, including mice, nonhuman primates, rabbits, and guinea pigs, are instrumental for mechanistic insights into the pathogenesis of viral infections during pregnancy and identification of targetable treatments to improve health outcomes of pregnant individuals and offspring.

Preeclampsia in pregnant women with COVID-19: a prospective cohort study from two tertiary hospitals in Southern Brazil

Background

COVID-19 is an infectious pathology that shows vascular changes during pregnancy, as well as in the placentas. The main objectives of this study were to estimate the prevalence and the risk factors for preeclampsia in hospitalized pregnant women with COVID-19. As well as comparing maternal and perinatal outcomes in hospitalized pregnant women with COVID-19 and preeclampsia with those without preeclampsia.

Methods

Prospective cohort study of 100 hospitalized pregnant women from two tertiary hospitals, diagnosed with COVID-19, and divided into two groups: PE+ group (pregnant women with COVID-19 and preeclampsia) and PE- group (pregnant women with COVID-19 without preeclampsia). These pregnant women had prevalence, risk factors, maternal and perinatal data analyzed.

Results

The prevalence of preeclampsia was 11%. Severe COVID-19 was the main risk factor for preeclampsia (OR = 8.18 [CI 1.53-43.52]), as well as fetal growth restriction was the main perinatal outcome (OR = 8.90 [CI 1.52-38.4]). Comorbidities were more frequent in the PE+ group (63.6% vs 31.5%, p = 0.03), as well as prematurity (81.8% vs 41.6%, p = 0.02), low birth weight (63.6% vs 24.7%, p = 0.01), and the need for neonatal intensive care admission of the newborn (63.6% vs 27.0%, p = 0.03). Pregnant women with PE had twice as long a length of stay in the intensive care unit (RR = 2.35 [CI 1.34-4.14]). Although maternal mortality was more frequent among pregnant women with PE, it was not statistically significant.

Conclusions

Prevalence of preeclampsia in hospitalized pregnant women with COVID-19 was 11%. Severe COVID-19 was the main risk factor for preeclampsia and associated comorbidities increased the risk for developing preeclampsia. Long length of stay in the intensive care unit was the main maternal outcome and fetal growth restriction was the main perinatal outcome of preeclampsia.

BNT162b2 COVID-19 vaccine does not affect fertility as explored in a pilot study of women undergoing IVF treatment

BACKGROUND

The COVID-19 pandemic spreads worldwide, causing devastating consequences. BioNTech (BioNTech SE, Mainz, Germany) and Pfizer's (Pfizer Inc., Brooklyn, NY, USA) BNT162b2 vaccine was one of the first vaccines to receive emergency-use authorization. However, its impact on women's fertility has not been primarily assessed leading to spread of unfounded rumors, causing vaccine hesitancy. We investigate the possible impact of BNT162b2 COVID-19 vaccine on in-vitro fertilization (IVF) outcomes.

METHODS

We compared data from 42 women undergoing their first IVF following 2 doses of BNT162b2 vaccination to 42 unvaccinated women undergoing their first IVF. The first outcome consisted of the pregnancy based on first hCG value; secondary outcomes were IVF cycle outcomes. A second analysis was done on 29 paired patients from both groups based on age, FSH, and the indication for IVF.

RESULTS

We report different levels of the pregnancy formation; oocyte's development: numbers of oocytes retrieved (9.3±6.8 vs. 11.5±7.9, P=0.19) and matured (6.9±4.8 vs. 9.1±6.6, P=0.14), and embryonal stage: fertilization rates (64.1±26.6 vs. 66.3±23.3, P=0.14), the quantity (4.3±3.2 vs. 5.7±4.4, P=0.23) and qualities of embryos (good/fair/poor) at day 3 were comparable. The analysis showed no significant difference between the groups, and the odds for pregnancy were similar (OR=0.9, 95% CL [0.3-2.8] P value 0.833).

CONCLUSIONS

From our results, this vaccine does not affect IVF performance and outcomes from the early stage of oocyte development through to the early beginning of pregnancy; therefore, it seems that the BNT162b2 vaccine does not compromise women's fertility.

IgG antibody levels against the SARS-CoV-2 spike protein in mother-child dyads after COVID-19 vaccination

PURPOSE

We aimed to assess IgG antibodies against the SARS-CoV-2 spike protein (anti-SARS-CoV-2 S IgG) in vaccinated mothers and their infants at delivery and 2-3 months of age.

METHODS

We conducted a prospective study on mothers who received at least one dose of the COVID-19 vaccine (Pfizer-BNT162b2, Moderna mRNA-1273, or Oxford-AstraZeneca ChAdOx1-S) during pregnancy and on their infants. The baseline was at the time of delivery (n = 93), and the end of follow-up was 2 to 3 months post-partum (n = 53). Serum anti-SARS-CoV-2 S IgG titers and ACE2 binding inhibition levels were quantified by immunoassays.

RESULTS

Mothers and infants had high anti-SARS-CoV-2 S IgG titers against the B.1 lineage at birth. However, while antibody titers were maintained at 2-3 months post-partum in mothers, they decreased significantly in infants (p < 0.001). Positive and significant correlations were found between anti-SARS-CoV-2 S IgG titers and ACE2-binding inhibition levels in mothers and infants at birth and 2-3 months post-partum (r > 0.8, p < 0.001). Anti-S antibodies were also quantified for the Omicron variant at 2-3 months post-partum. The antibody titers against Omicron were significantly lower in mothers and infants than those against B.1 (p < 0.001). Again, a positive correlation was observed for Omicron between IgG titers and ACE2-binding inhibition both in mothers (r = 0.818, p < 0.001) and infants (r = 0.386, p < 0.005). Previous SARS-CoV-2 infection and COVID-19 vaccination near delivery positively impacted anti-SARS-CoV-2 S IgG levels.

CONCLUSIONS

COVID-19 mRNA vaccines induce high anti-SARS-CoV-2 S titers in pregnant women, which can inhibit the binding of ACE2 to protein S and are efficiently transferred to the fetus. However, there was a rapid decrease in antibody levels at 2 to 3 months post-partum, particularly in infants.

Obstetric Complications and Birth Outcomes After Antenatal Coronavirus Disease 2019 (COVID-19) Vaccination

OBJECTIVE

To evaluate the association between antenatal messenger RNA (mRNA) coronavirus disease 2019 (COVID-19) vaccination and risk of adverse pregnancy outcomes.

METHODS

This was a retrospective cohort study of individuals with singleton pregnancies with live deliveries between June 1, 2021, and January 31, 2022, with data available from eight integrated health care systems in the Vaccine Safety Datalink. Vaccine exposure was defined as receipt of one or two mRNA COVID-19 vaccine doses (primary series) during pregnancy. Outcomes were preterm birth (PTB) before 37 weeks of gestation, small-for-gestational age (SGA) neonates, gestational diabetes mellitus (GDM), gestational hypertension, and preeclampsia-eclampsia-HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome. Outcomes in individuals vaccinated were compared with those in propensity-matched individuals with unexposed pregnancies. Adjusted hazard ratios (aHRs) and 95% CIs were estimated for PTB and SGA using a time-dependent covariate Cox model, and adjusted relative risks (aRRs) were estimated for GDM, gestational hypertension, and preeclampsia-eclampsia-HELLP syndrome using Poisson regression with robust variance.

RESULTS

Among 55,591 individuals eligible for inclusion, 23,517 (42.3%) received one or two mRNA COVID-19 vaccine doses during pregnancy. Receipt of mRNA COVID-19 vaccination varied by maternal age, race, Hispanic ethnicity, and history of COVID-19. Compared with no vaccination, mRNA COVID-19 vaccination was associated with a decreased risk of PTB (rate: 6.4 [vaccinated] vs 7.7 [unvaccinated] per 100, aHR 0.89; 95% CI, 0.83-0.94). Messenger RNA COVID-19 vaccination was not associated with SGA (8.3 vs 7.4 per 100; aHR 1.06, 95% CI, 0.99-1.13), GDM (11.9 vs 10.6 per 100; aRR 1.00, 95% CI, 0.90-1.10), gestational hypertension (10.8 vs 9.9 per 100; aRR 1.08, 95% CI, 0.96-1.22), or preeclampsia-eclampsia-HELLP syndrome (8.9 vs 8.4 per 100; aRR 1.10, 95% CI, 0.97-1.24).

CONCLUSION

Receipt of an mRNA COVID-19 vaccine during pregnancy was not associated with an increased risk of adverse pregnancy outcomes; this information will be helpful for patients and clinicians when considering COVID-19 vaccination in pregnancy.

Clinical Characteristics, Outcomes, and Risk Factors for Mortality in Pregnant/Puerperal Women with COVID-19 Admitted to ICU in Turkey: A Multicenter, Retrospective Study from a Middle-Income Country

BACKGROUND

Coronaviruses have been the cause of 3 major outbreaks during the last 2 decades. Information on coronavirus diseases in pregnant women is limited, and even less is known about seriously ill pregnant women. Data are also lacking regarding the real burden of coronavirus disease 2019 (COVID-19) infection in pregnant women from low/middle-income countries. The aim of this study was to determine the characteristics and clinical course of COVID-19 in pregnant/puerperal women admitted to ICUs in Turkey.

METHODS

This was a national, multicenter, retrospective study. The study population comprised all SARS-CoV-2-infected pregnant/puerperal women admitted to participating ICUs between 1 March 2020 and 1 January 2022. Data regarding demographics, comorbidities, illness severity, therapies, extrapulmonary organ injuries, non-COVID-19 infections, and maternal and fetal/neonatal outcomes were recorded. LASSO logistic regression and multiple logistic regression analyses were used to identify predictive variables in terms of ICU mortality.

RESULTS

A total of 597 patients (341 pregnant women, 255 puerperal women) from 59 ICUs in 44 hospitals were included and of these patients, 87.1% were unvaccinated. The primary reason for ICU admission was acute hypoxemic respiratory failure in 522 (87.4%), acute hypoxemic respiratory failure plus shock in 14 (2.3%), ischemic cerebrovascular accident (CVA) in 5 (0.8%), preeclampsia/eclampsia/HELLP syndrome in 6 (1.0%), and post-caesarean follow-up in 36 (6.0%). Nonsurvivors were sicker than survivors upon ICU admission, with higher APACHE II (p < 0.001) and SOFA scores (p < 0.001). A total of 181 (30.3%) women died and 280 (46.6%) had received invasive mechanical ventilation (IMV). Myocardial injury, the highest SOFA score during ICU stay, LDH levels on admission, the highest levels of AST during ICU stay, average daily dose of corticosteroids, IMV, prophylactic dose anticoagulation (compared with therapeutic dose anticoagulation), PaO2/FiO2 ratio <100, pulmonary embolism, and shock were identified as predictors of mortality. Rates of premature birth (46.4%), cesarean section (53.7%), fetal distress (15.3%), stillbirth (6.5%), and low birth weight (19.4%) were high. Rates of neonatal death (8%) and respiratory distress syndrome (21%) were also high among live-born infants.

CONCLUSIONS

Severe/critical COVID-19 infection during the pregnancy/puerperal period was associated with high maternal mortality and fetal/neonatal complication rates in Turkey.

Extracellular vesicles alter trophoblast function in pregnancies complicated by COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and resulting coronavirus disease (COVID-19) causes placental dysfunction, which increases the risk of adverse pregnancy outcomes. While abnormal placental pathology resulting from COVID-19 is common, direct infection of the placenta is rare. This suggests that pathophysiology associated with maternal COVID-19, rather than direct placental infection, is responsible for placental dysfunction and alteration of the placental transcriptome. We hypothesized that maternal circulating extracellular vesicles (EVs), altered by COVID-19 during pregnancy, contribute to placental dysfunction. To examine this hypothesis, we characterized maternal circulating EVs from pregnancies complicated by COVID-19 and tested their effects on trophoblast cell physiology in vitro . We found that the gestational timing of COVID-19 is a major determinant of circulating EV function and cargo. In vitro trophoblast exposure to EVs isolated from patients with an active infection at the time of delivery, but not EVs isolated from Controls, altered key trophoblast functions including hormone production and invasion. Thus, circulating EVs from participants with an active infection, both symptomatic and asymptomatic cases, can disrupt vital trophoblast functions. EV cargo differed between participants with COVID-19 and Controls, which may contribute to the disruption of the placental transcriptome and morphology. Our findings show that COVID-19 can have effects throughout pregnancy on circulating EVs and circulating EVs are likely to participate in placental dysfunction induced by COVID-19.

Impact of COVID-19 on pregnancy outcomes during delivery admissions: a nationwide analysis with clinical implications

Background

The available literature indicates a link between SARS-CoV-2 infection during pregnancy and a heightened probability of experiencing negative outcomes for both the pregnant patient and the developing fetus. We compared clinical outcomes of pregnant patients with or without COVID-19 hospitalized during delivery.

Methods

Multivariate logistic regression analysis was used to compare outcomes and was adjusted for patient-related, hospital-related, and illness severity indicators.

Results

We identified a total of 3,447,771 pregnant patients admitted between January 1, 2020 and December 31, 2020; 1.3% (n = 46,050) had COVID-19. COVID-19-positive patients had higher rates of in-hospital mortality (0.15% vs 0.05%, adjusted odds ratio [aOR] 5.97, 95% confidence interval [CI] 2.5-14.25, P < 0.001), mechanical ventilation (0.9% vs 0.05%, aOR 14.2, 95% CI 10.7-18.76, P < 0.001), vasopressor use (0.26% vs 0.14%, aOR 1.47, 95% CI 1.07-2.02, P = 0.01), and perinatal maternal complications like preeclampsia (9.66% vs 7.04%, aOR 1.29, 95% CI 1.2-1.39, P < 0.001) and hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome (0.53% vs 0.26%, aOR 1.93, 95% CI 1.43-2.61, P < 0.001) than COVID-19-negative patients.

Discussion

Clinicians should be aware of the heightened risk of complications in pregnant patients with COVID-19 and consider strategies to mitigate them.

SARS-CoV-2 Infection in Pregnant Women With Hypothyroidism

Background Severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) infection has been linked to increased maternal and fetal morbidity and mortality, as evidenced by numerous studies. Given the potential exacerbation of autoimmune diseases during viral infections, maternal and fetal complications such as preterm birth, low birth weight, or preeclampsia, often observed in pregnancies involving autoimmune thyroiditis with hypothyroidism, may be further aggravated. This study seeks to ascertain whether the association between viral infection and hypothyroidism contributes to an increase in adverse pregnancy outcomes. Methods This study included a cohort of 145 pregnant women with SARS-CoV-2 infection, who delivered in the Department of Obstetrics and Gynecology of the University Emergency Hospital in Bucharest, Romania, between January 1, 2020, and December 31, 2022. The participants were divided into two groups depending on the presence of autoimmune thyroiditis with hypothyroidism. We examined the maternal and fetal demographic parameters, paraclinical laboratory parameters, and outcomes, aiming to identify disparities between the two groups. Results Among the 145 SARS-CoV-2-positive pregnant women, the prevalence of hypothyroidism was 8.96%, with 13 cases reported. In the hypothyroidism group, the mean age of coronavirus disease 2019 (COVID-19) patients was higher (34.07 ± 5.18 years vs. 29.25 ± 6.23 years), as was the number of cases of investigated pregnancies, 12 (92.31%) vs. 91 (68.94%). There was no statistically significant correlation observed between fetal weight at birth, one-minute Apgar score, neonatal intensive care unit (NICU) admission, or intrauterine growth restriction between the two groups. Nevertheless, a case of stillbirth was recorded in the hypothyroidism group. The presence of thyroid pathology did not exacerbate the progression of the viral infection, as evidenced by the absence of cases of preeclampsia, ICU admission, or SARS-CoV-2 pneumonia. Conversely, the presence of hypothyroidism in pregnant women with SARS-CoV-2 infection was associated with lower uric acid levels and a slight decrease in international normalised ratio (INR) values. Additionally, there was a significant negative association between uric acid levels and the one-minute Apgar score in the hypothyroidism group, while no such correlations were observed in the other group. Furthermore, there was a statistically significant correlation between intrauterine growth restriction and uric acid values, as well as between the one-minute Apgar score and INR parameters, in both groups. Conclusion The link between SARS-CoV-2 infection and hypothyroidism does not appear to increase the risk of preterm birth, intrauterine growth restriction, or low fetal weight at birth. However, it may be associated with a higher risk of stillbirth. The presence of hypothyroidism in pregnant women with COVID-19 correlates with lower maternal uric acid levels and a slight decrease in INR values. The one-minute Apgar score correlates with the level of uric acid in pregnant women with SARS-CoV-2 infection and hypothyroidism.

Low absolute risk of thrombotic and cardiovascular events in outpatient pregnant women with COVID-19

INTRODUCTION

Pregnancy may contribute to an excess risk of thrombotic or cardiovascular events. COVID-19 increases the risk of these events, although the risk is relatively limited among outpatients. We sought to determine whether outpatient pregnant women with COVID-19 are at a high risk for cardiovascular or thrombotic events.

MATERIALS & METHODS

We analyzed pregnant outpatients with COVID-19 from the multicenter CORONA-VTE-Network registry. The main study outcomes were a composite of adjudicated venous or arterial thrombotic events, and a composite of adjudicated cardiovascular events. Events were assessed 90 days after the COVID-19 diagnosis and reported for non-pregnant women ≤45 years, and for men ≤45 years, as points of reference.

RESULTS

Among 6585 outpatients, 169 were pregnant at diagnosis. By 90-day follow-up, two pregnant women during the third trimester had lower extremity venous thrombosis, one deep and one superficial vein thrombosis. The cumulative incidence of thrombotic events was 1.20 % (95 % confidence interval [CI]: 0.0 to 2.84 %). Respective rates were 0.47 % (95 % CI: 0.14 % to 0.79 %) among non-pregnant women, and 0.49 % (95 % CI: 0.06 % to 0.91 %) among men ≤45 years. No non-thrombotic cardiovascular events occurred in pregnant women. The rates of cardiovascular events were 0.53 % (95 % CI: 0.18 to 0.87) among non-pregnant women, and 0.68 % (95 % CI: 0.18 to 1.18) in men aged ≤45 years.

CONCLUSIONS

Thrombotic and cardiovascular events are rare among outpatients with COVID-19. Although a higher event rate among outpatient pregnant women cannot be excluded, the absolute event rates are low and do not warrant population-wide cardiovascular interventions to optimize outcomes.

Comparison of Anti-SARS-CoV-2-Specific Antibody Signatures in Maternal and Infant Blood after COVID-19 Infection versus COVID-19 Vaccination during Pregnancy

OBJECTIVE

 The Advisory Committee on Immunization Practices and The American College of Obstetricians and Gynecologists recommend coronavirus disease 2019 (COVID-19) vaccine for pregnant persons to prevent severe illness and death. The objective was to examine levels of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG, IgM, and IgA against spike protein receptor binding domain (RBD) and nucleocapsid protein (NCP) in maternal and infant/cord blood at delivery after COVID 19 vaccination compared with SARS-CoV-2 infection at in mother-infant dyads at specified time points.

STUDY DESIGN

 Mothers with SARS-CoV-2 infection (n = 31) or COVID-19 vaccination (n = 25) during pregnancy were enrolled between July 2020 and November 2021. Samples were collected at delivery and IgG, IgM, and IgA to RBD of spike and NCPs compared in the infected and vaccinated groups. Timing of infection/vaccination prior to delivery and correlation with antibody levels was performed.

RESULTS

 The majority of participants received vaccination within 90 days of delivery and over half received the Pfizer BioNTech vaccine. There were no significant correlations between antibody levels and timing of infection or vaccination. Infant IgG levels to the RBD domain of spike protein were higher in the vaccinated group (n = 25) as compared with the infants born to mothers with infection (n = 31). Vaccination against COVID-19 during pregnancy was associated with detectable maternal and infant anti-RBD IgG levels at delivery irrespective of the timing of vaccination.

CONCLUSION

 Timing of vaccination had no correlation to the antibody levels suggesting that the timing of maternal vaccination in the cohort did not matter. There was no IgM detected in infants from vaccinated mothers. Infants from vaccinated mothers had robust IgG titers to RBD, which have a lasting protective effect in infants.

KEY POINTS

· COVID-19 vaccination during pregnancy had detectable antibody.. · No correlation between antibody levels and timing of vaccination.. · Infants from vaccinated mothers had robust IgG titers to RBD..

Thrombotic Markers in Pregnant Patients with and without SARS-CoV-2 Infection

BACKGROUND

Coronavirus disease 2019 (COVID-19) is associated with coagulation abnormalities and increased risk for venous and arterial thrombi. This study aimed to evaluate D-dimer levels and lupus anticoagulant (LAC) positivity in pregnant individuals with and without Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

STUDY DESIGN

This was a prospective cohort study of pregnant individuals delivering at a single academic institution from April 2020 to March 2022. Individuals with a positive SARS-CoV-2 result during pregnancy were compared with a convenience sample of those without a positive SARS-CoV-2 result. For individuals with SARS-CoV-2 infection, severity was assessed based on the National Institutes of Health classification system. The primary outcome was D-dimer level measured during delivery admission. The secondary outcomes were LAC positivity and thromboembolic events. Outcomes were compared between individuals with and without a positive SARS-CoV-2 result, and further by disease severity.

RESULTS

Of 98 participants, 77 (78.6%) were SARS-CoV-2 positive during pregnancy. Among individuals with SARS-CoV-2 infection, severity was asymptomatic in 20 (26.0%), mild in 13 (16.9%), moderate in 4 (5.2%), severe in 38 (49.4%), and critical in 2 (2.6%). The D-dimer concentration at delivery did not significantly differ between those with a SARS-CoV-2 positive result compared with those without (mean 2.03 µg/mL [95% confidence interval {CI} 1.72-2.40] vs. 2.37 µg/mL [95% CI 1.65-3.40]; p = 0.43). Three individuals (4%) with SARS-CoV-2 infection and none (0%) without infection were LAC positive (p = 0.59). There were no clinically apparent thromboses in either group. D-dimer concentrations and LAC positive results did not differ by COVID-19 severity.

CONCLUSION

Thrombotic markers did not differ in pregnant individuals by SARS-CoV-2 infection; however, high rates of LAC positivity were detected.

KEY POINTS

· Thrombotic markers did not differ in pregnant individuals by SARS-CoV-2 infection.. · Higher than expected rates of LAC positivity were detected.. · There were no clinically apparent thromboses..

Population-Level Study on Fetal Deaths and Preterm Births during SARS-CoV-2 Pandemic in the State of Michigan

OBJECTIVE

The aim of the study is to explore the effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic on preterm birth at different gestational ages and fetal death in the state of Michigan.

STUDY DESIGN

Data on live births and fetal deaths in the state of Michigan from March to November in the years 2017 through 2020 were obtained from Michigan Department of Health and Human Services (MDHHS). Preterm birth rate, fetal death rate (per 1,000 live births) overall and stratified by race and maternal comorbidities during the period of pandemic (March-November 2020) were compared with the same period (March-November) in the prepandemic years (2017-2019).

RESULTS

Of 328,879 live births and 1,470 fetal deaths during the study period, 77,983 live births and 242 fetal deaths were reported in 2020. Compared with prepandemic years, fetal death rate per 1,000 live births was significantly lower in 2020 (3.1 vs. 4.7 [2017], 5.2 [2018], 4.4 [2019], p-value <0.001). The adjusted risk for fetal death in 2020 was decreased (odds ratio [OR] = 0.64 [95% confidence interval (CI): 0.56-0.74], p <0.0001), compared with prepandemic years. Fetal death was significantly associated with African-American race, pregnancy hypertension and prepregnancy diabetes. No significant difference in the proportion of preterm births (<37 weeks' gestation) was noted between pandemic and prepandemic years (9.9 vs. 10.0%, p = 0.50). There was no significant difference in the risk of preterm birth across gestational age strata (<28, 28-316/7, 32-366/7, 37-416/7, and >42 weeks) between pandemic and prepandemic years on multinomial analysis. Significant associations with preterm birth across all years included African American race, lower level of maternal education, pregnancy-induced hypertension, chronic hypertension, prepregnancy diabetes, congenital anomalies, previous preterm birth, and prolonged rupture of membranes >12 hours.

CONCLUSION

Fetal death rate was significantly lower whereas preterm births remained unchanged during pandemic in comparison with prepandemic years in the state of Michigan.

KEY POINTS

· A decrease in fetal death rate was noted during SARS CoV-2 pandemic in the State of Michigan.. · Overall state-wide rates of preterm birth did not change in 2020, compared to previous years.. · Significant risk factors associated with preterm birth and fetal deaths did not differ between prepandemic and pandemic years..

Placental inflammation in a fetal demise of a SARS-CoV-2-asymptomatic, COVID-19-unvaccinated pregnant woman: a case-report

BACKGROUND

Intrauterine fetal demise is a recognized complication of coronavirus disease 2019 in pregnant women and is associated with histopathological placental lesions. The pathological mechanism and virus-induced immune response in the placenta are not fully understood. A detailed description of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced inflammation in the placenta during fetal demise is crucial for improved clinical management.

CASE PRESENTATION

We report the case of a 27-week gestation SARS-CoV-2-asymptomatic unvaccinated pregnant woman without comorbidities or other risk factors for negative pregnancy outcomes with a diagnosis of intrauterine fetal demise. Histopathological findings corresponded to patterns of subacute inflammation throughout the anatomic compartments of the placenta, showing severe chorioamnionitis, chronic villitis and deciduitis, accompanied by maternal and fetal vascular malperfusion. Our immunohistochemistry results revealed infiltration of CD68+ macrophages, CD56+ Natural Killer cells and scarce CD8+ T cytotoxic lymphocytes at the site of placental inflammation, with the SARS-CoV-2 nucleocapsid located in stromal cells of the chorion and chorionic villi, and in decidual cells.

CONCLUSION

This case describes novel histopathological lesions of inflammation with infiltration of plasma cells, neutrophils, macrophages, and natural killer cells associated with malperfusion in the placenta of a SARS-CoV-2-infected asymptomatic woman with intrauterine fetal demise. A better understanding of the inflammatory effects exerted by SARS-CoV-2 in the placenta will enable strategies for better clinical management of pregnant women unvaccinated for SARS-CoV-2 to avoid fatal fetal outcomes during future transmission waves.

SARS-CoV-2 infection by trimester of pregnancy and adverse perinatal outcomes: a Mexican retrospective cohort study

OBJECTIVE

Conflicting evidence for the association between COVID-19 and adverse perinatal outcomes exists. This study examined the associations between maternal COVID-19 during pregnancy and adverse perinatal outcomes including preterm birth (PTB), low birth weight (LBW), small-for-gestational age (SGA), large-for-gestational age (LGA) and fetal death; as well as whether the associations differ by trimester of infection.

DESIGN AND SETTING

The study used a retrospective Mexican birth cohort from the Instituto Mexicano del Seguro Social (IMSS), Mexico, between January 2020 and November 2021.

PARTICIPANTS

We used the social security administrative dataset from IMSS that had COVID-19 information and linked it with the IMSS routine hospitalisation dataset, to identify deliveries in the study period with a test for SARS-CoV-2 during pregnancy.

OUTCOME MEASURES

PTB, LBW, SGA, LGA and fetal death. We used targeted maximum likelihood estimators, to quantify associations (risk ratio, RR) and CIs. We fit models for the overall COVID-19 sample, and separately for those with mild or severe disease, and by trimester of infection. Additionally, we investigated potential bias induced by missing non-tested pregnancies.

RESULTS

The overall sample comprised 17 340 singleton pregnancies, of which 30% tested positive. We found that those with mild COVID-19 had an RR of 0.89 (95% CI 0.80 to 0.99) for PTB and those with severe COVID-19 had an RR of 1.53 (95% CI 1.07 to 2.19) for LGA. COVID-19 in the first trimester was associated with fetal death, RR=2.36 (95% CI 1.04, 5.36). Results also demonstrate that missing non-tested pregnancies might induce bias in the associations.

CONCLUSIONS

In the overall sample, there was no evidence of an association between COVID-19 and adverse perinatal outcomes. However, the findings suggest that severe COVID-19 may increase the risk of some perinatal outcomes, with the first trimester potentially being a high-risk period.

Association between the degree of severity of COVID-19 infection during pregnancy and preterm premature rupture of membranes in a level III hospital in Peru

OBJECTIVES.

To determine the association between the degree of severity of COVID-19 infection during pregnancy and preterm premature rupture of membranes (PPROM) in a level III hospital in Peru.

MATERIALS AND METHODS.

Cross-sectional, analytical and observational study in women older than 18 years diagnosed with COVID-19 infection during pregnancy, between the years 2020 and 2022. Clinical and obstetric variables were collected. The chi-square and Fisher's exact tests were used for the descriptive analysis. For the multivariate analysis, we calculated the prevalence ratio by using Poisson regression in crude and adjusted models. All statistical tests were performed considering a value of p<0.05 as significant and with a confidence level of 95%.

RESULTS.

We analyzed data from 163 pregnant women with COVID-19, of which 9.2% had PPROM; all were symptomatic cases. Mild COVID-19 cases were 1.10 times more likely to have PPROM (RPa=1.10; 95%CI: 1.02-1.18) and moderate/severe cases were 1.64 times more likely (RPa=1.64; 95%CI: 1.43-1.87), compared to asymptomatic cases.

CONCLUSIONS.

We identified that a higher degree of severity of COVID-19 infection during pregnancy was associated with a higher probability of having PPROM.

Impact of COVID-19 and Vaccination During Pregnancy on Placenta-Mediated Complications (COVIGRO Study)

OBJECTIVES

COVID-19 has been associated with preterm birth (PTB) and placental-mediated complications, including fetal growth restriction and preeclampsia (PE). This study aimed to estimate the impact of COVID-19 and vaccination on adverse pregnancy outcomes and markers of placental function.

METHODS

We performed a study on a prospective cohort of women recruited in the first trimester of pregnancy during the early COVID-19 pandemic period (December 2020 to December 2021). At each trimester of pregnancy, the assessment included a questionnaire on COVID-19 and vaccination status; serological tests for COVID-19 (for asymptomatic infection); measurement of placental growth factor (PlGF) and soluble fms-like tyrosine kinase 1 (sFlt-1) in maternal blood; measurement of mean uterine artery pulsatility index (UtA-PI); and pregnancy outcomes (PTB, PE, birth weight below the fifth and the tenth percentile).

RESULTS

Among 788 patients with complete data, we observed 101 (13%) cases of symptomatic infection and 74 (9%) cases of asymptomatic infection with SARS-CoV-2. Most cases (73%) of infection were among women with previous vaccination or COVID-19 infection before pregnancy. COVID-19 infection was not associated with adverse pregnancy outcomes, abnormal fetal growth, sFlt-1/PlGF ratio, or mean UtA-PI. Vaccination during pregnancy did not influence these outcomes either. We observed no case of severe COVID-19 infection requiring respiratory support.

CONCLUSION

Mild symptomatic or asymptomatic COVID-19 during pregnancy did not influence the risk of adverse pregnancy outcomes and the markers of placental function in predominantly vaccinated women. Fetal growth monitoring is unlikely to be mandatory in women with mild symptoms of COVID-19.

Maternal and Newborn Outcomes of SARS-CoV-2/COVID-19 and Pregnancy: Parallels and Contrasts with Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome

Purpose of Review

Our review aims to compare and contrast Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome and SARS-CoV-2/COVID-19's impact on maternal and neonatal outcomes. We have made significant progress in Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome prevention and treatment over the last few decades. Drawing on empirical evidence with past public health crises can offer valuable insights into dealing with current and future pandemics. Therefore, it is imperative to conduct a comparative analysis of the resemblances and disparities existing between Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome and SARS-CoV-2/COVID-19.This research endeavor represents a pioneering and all-encompassing examination, aiming to discern and comprehend the parallels and contrasts in the respective impacts of SARS-CoV-2 and Human Immunodeficiency Virus on pregnancy.

Recent Findings

Based on the current evidence, there is no indication that pregnancy increases women's susceptibility to acquiring Human Immunodeficiency Virus or SARS-CoV-2. Nevertheless, the state of being pregnant was correlated with the worsening of diseases and their progression. Both Human Immunodeficiency Virus and SARS-CoV-2 pose increased risks of maternal mortality and several obstetric complications, including premature birth and pre-eclampsia. While the vertical transmission of Human Immunodeficiency Virus is well-established, a comprehensive understanding of the vertical transmission of SARS-CoV-2 remains elusive, emphasizing the need for further investigations. Initial data suggest low SARS-CoV-2 vertical transmission rates in the setting of proper preventative interventions and universal screening. A cesarean delivery could reduce the risk of mother-to-child transmission in Human Immunodeficiency Virus-infected women with high viral loads or poor adherence to antiretroviral therapy (ART). However, it did not offer additional protection for Human Immunodeficiency Virus-infected women who adhered to Adherence to Antiretroviral Therapy or those with COVID-19. Human Immunodeficiency Virus and SARS-CoV-2 were linked to neonatal complications such as stillbirth, low birth weight, and neonatal intensive care unit (ICU) admissions. The universal testing of both pregnant patients and neonates is an effective strategy to prevent the spread and complications of both Human Immunodeficiency Virus and SARS-CoV-2. Human Immunodeficiency Virus control largely relies on preventing vertical transmission and medications during pregnancy and postpartum, whereas safety behaviors and vaccines have proven effective in preventing SARS-CoV-2 vertical transmissions.

Summary

This review aims to compare and contrast the impact of Human Immunodeficiency Virus and SARS-CoV-2 on pregnancy outcomes, vertical transmissions, delivery modalities, neonatal outcomes, and clinical management. SARS-CoV-2 and Human Immunodeficiency Virus were associated with significant obstetric-related complications, making close clinical monitoring and preparation essential. Integration of SARS-CoV-2/COVID-19 management with reproductive health services is crucial to ensuring maternal and neonatal outcomes. Our review is not only the first to establish a groundwork for the current state of knowledge and its clinical implications on this topic, but it also sheds new insights for future research directions.Comparing Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome and SARS-CoV-2 in terms of their impact on maternal and neonatal outcomes provides valuable insights despite their differences. Leveraging Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome research can help understand SARS-CoV-2 effects on pregnancy. Both infections pose risks to pregnant individuals and their fetuses, leading to increased maternal mortality and complications. Identifying common patterns and risk factors can improve clinical management for pregnant individuals with SARS-CoV-2. While a direct observational study for this comparison may not be feasible, comparing with Human Immunodeficiency Virus offers an ethical and practical approach. However, specific studies on SARS-CoV-2 are still necessary to gather detailed data on maternal and fetal outcomes.

Implication of viruses in the etiology of preeclampsia

Preeclampsia is one of the most common disorders that poses threat to both mothers and neonates and a major contributor to perinatal morbidity and mortality worldwide. Viral infection during pregnancy is not typically considered to cause preeclampsia; however, syndromic nature of preeclampsia etiology and the immunomodulatory effects of viral infections suggest that microbes could trigger a subset of preeclampsia. Notably, SARS-CoV-2 infection is associated with an increased risk of preeclampsia. Herein, we review the potential role of viral infections in this great obstetrical syndrome. According to in vitro and in vivo experimental studies, viral infections can cause preeclampsia by introducing poor placentation, syncytiotrophoblast stress, and/or maternal systemic inflammation, which are all known to play a critical role in the development of preeclampsia. Moreover, clinical and experimental investigations have suggested a link between several viruses and the onset of preeclampsia via multiple pathways. However, the results of experimental and clinical research are not always consistent. Therefore, future studies should investigate the causal link between viral infections and preeclampsia to elucidate the mechanism behind this relationship and the etiology of preeclampsia itself.

The association of post-embryo transfer SARS-CoV-2 infection with early pregnancy outcomes in in vitro fertilization: a prospective cohort study

BACKGROUND

The influence of SARS-CoV-2 infection after embryo transfer on early pregnancy outcomes in in vitro fertilization or intracytoplasmic sperm injection-embryo transfer treatment remains inadequately understood. This knowledge gap endures despite an abundance of studies investigating the repercussions of preceding SARS-CoV-2 infection on early pregnancy outcomes in spontaneous pregnancies.

OBJECTIVE

This study aimed to investigate the association between SARS-CoV-2 infection within 10 weeks after embryo transfer and early pregnancy outcomes in patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment.

STUDY DESIGN

This prospective cohort study was conducted at a single public in vitro fertilization center in China. Female patients aged 20 to 39 years, with a body mass index ranging from 18 to 30 kg/m2, undergoing in vitro fertilization/intracytoplasmic sperm injection treatment, were enrolled between September 2022 and December 2022, with follow-up extended until March 2023. The study tracked SARS-CoV-2 infection time (≤14 days, ≤28 days, and ≤10 weeks after embryo transfer), symptoms, vaccination status, the interval between vaccination and embryo transfer, and early pregnancy outcomes, encompassing biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate. The study used single-factor analysis and multivariate logistic regression to examine the association between SARS-CoV-2 infection status, along with other relevant factors, and the early pregnancy outcomes.

RESULTS

A total of 857 female patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment were analyzed. In the first stage, SARS-CoV-2 infection within 14 days after embryo transfer did not have a significant negative association with the biochemical pregnancy rate (adjusted odds ratio, 0.74; 95% confidence interval, 0.51-1.09). In the second stage, SARS-CoV-2 infection within 28 days after embryo transfer had no significant association with the implantation rate (36.6% in infected vs 44.0% in uninfected group; P=.181). No statistically significant association was found with the clinical pregnancy rate after adjusting for confounding factors (adjusted odds ratio, 0.69; 95% confidence interval, 0.56-1.09). In the third stage, SARS-CoV-2 infection within 10 weeks after embryo transfer had no significant association with the early miscarriage rate (adjusted odds ratio, 0.77; 95% confidence interval, 0.35-1.71).

CONCLUSION

Our study suggests that SARS-CoV-2 infection within 10 weeks after embryo transfer may not be negatively associated with the biochemical pregnancy rate, implantation rate, clinical pregnancy rate, and early miscarriage rate in patients undergoing in vitro fertilization/intracytoplasmic sperm injection treatment. It is important to note that these findings are specific to the target population of in vitro fertilization/intracytoplasmic sperm injection patients aged 20 to 39 years, without previous SARS-CoV-2 infection, and with a body mass index of 18 to 30 kg/m2. This information offers valuable insights, addressing current concerns and providing a clearer understanding of the actual risk associated with SARS-CoV-2 infection after embryo transfer.

Efficacy and Clinical Outcomes of mRNA COVID-19 Vaccine in Pregnancy: A Systematic Review and Meta-Analysis

BACKGROUND

The world has witnessed one of the largest pandemics, dubbed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As of December 2020, the USA alone reported 98,948 cases of coronavirus disease 2019 (COVID-19) infection during pregnancy, with 109 related maternal deaths. Current evidence suggests that unvaccinated pregnant women infected with SARS-CoV-2 are at a higher risk of experiencing complications related to COVID-19 compared to nonpregnant women. This review aimed to provide healthcare workers and non-healthcare workers with a comprehensive overview of the available information regarding the efficacy of vaccines in pregnant women.

SUMMARY

We performed a systematic review and meta-analysis following PRISMA guidelines. The search through the database for articles published between December 2019 and October 2021 was performed. A comprehensive search was performed in PubMed, Scopus, and EMBASE databases for research publications published between December 2019 and October 2021. We focused on original research, case reports, case series, and vaccination side effect by authoritative health institutions. Phrases used for the Medical Subject Heading [MeSH] search included ("COVID-19" [MeSH]) or ("Vaccine" [MeSH]) and ("mRNA" [MeSH]) and ("Pregnant" [MeSH]). Eleven studies were selected and included, with a total of 46,264 pregnancies that were vaccinated with mRNA-containing lipid nanoparticle vaccine from Pfizer/BioNTech and Moderna during pregnancy. There were no randomized trials, and all studies were observational (prospective, retrospective, and cross-sectional). The mean maternal age was 32.2 years, and 98.7% of pregnant women received the Pfizer COVID-19 vaccination. The local and systemic adverse effects of the vaccination in pregnant women were analyzed and reported. The local adverse effects of the vaccination (at least 1 dose) such as local pain, swelling, and redness were reported in 32%, 5%, and 1%, respectively. The systemic adverse effects such as fatigue, headaches, new onset or worsening of muscle pain, chills, fever, and joint pains were also reported in 25%, 19%, 18%, 12%, 11%, and 8%, respectively. The average birthweight was 3,452 g. Among these pregnancies, 0.03% were stillbirth and 3.68% preterm (<37 weeks) births.

KEY MESSAGES

The systemic side effect profile after administering the COVID-19 mRNA vaccine to pregnant women was similar to that in nonpregnant women. Maternal and fetal morbidity and mortality were lowered with the administration of either one or both the doses of the mRNA COVID-19 vaccination.

COVID-19 in pregnant women: a systematic review and meta-analysis on the risk and prevalence of pregnancy loss

BACKGROUND

Pregnant women infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are more likely to experience preterm birth and their neonates are more likely to be stillborn or admitted to a neonatal unit. The World Health Organization declared in May 2023 an end to the coronavirus disease 2019 (COVID-19) pandemic as a global health emergency. However, pregnant women are still becoming infected with SARS-CoV-2 and there is limited information available regarding the effect of SARS-CoV-2 infection in early pregnancy on pregnancy outcomes.

OBJECTIVE AND RATIONALE

We conducted this systematic review to determine the prevalence of early pregnancy loss in women with SARS-Cov-2 infection and compare the risk to pregnant women without SARS-CoV-2 infection.

SEARCH METHODS

Our systematic review is based on a prospectively registered protocol. The search of PregCov19 consortium was supplemented with an extra electronic search specifically on pregnancy loss in pregnant women infected with SARS-CoV-2 up to 10 March 2023 in PubMed, Google Scholar, and LitCovid. We included retrospective and prospective studies of pregnant women with SARS-CoV-2 infection, provided that they contained information on pregnancy losses in the first and/or second trimester. Primary outcome was miscarriage defined as a pregnancy loss before 20 weeks of gestation, however, studies that reported loss up to 22 or 24 weeks were also included. Additionally, we report on studies that defined the pregnancy loss to occur at the first and/or second trimester of pregnancy without specifying gestational age, and for second trimester miscarriage only when the study presented stillbirths and/or foetal losses separately from miscarriages. Data were stratified into first and second trimester. Secondary outcomes were ectopic pregnancy (any extra-uterine pregnancy), and termination of pregnancy. At least three researchers independently extracted the data and assessed study quality. We calculated odds ratios (OR) and risk differences (RDs) with corresponding 95% CI and pooled the data using random effects meta-analysis. To estimate risk prevalence, we performed meta-analysis on proportions. Heterogeneity was assessed by I2.

OUTCOMES

We included 120 studies comprising a total of 168 444 pregnant women with SARS-CoV-2 infection; of which 18 233 women were in their first or second trimester of pregnancy. Evidence level was considered to be of low to moderate certainty, mostly owing to selection bias. We did not find evidence of an association between SARS-CoV-2 infection and miscarriage (OR 1.10, 95% CI 0.81-1.48; I2 = 0.0%; RD 0.0012, 95% CI -0.0103 to 0.0127; I2 = 0%; 9 studies, 4439 women). Miscarriage occurred in 9.9% (95% CI 6.2-14.0%; I2 = 68%; 46 studies, 1797 women) of the women with SARS CoV-2 infection in their first trimester and in 1.2% (95% CI 0.3-2.4%; I2 = 34%; 33 studies; 3159 women) in the second trimester. The proportion of ectopic pregnancies in women with SARS-CoV-2 infection was 1.4% (95% CI 0.02-4.2%; I2 = 66%; 14 studies, 950 women). Termination of pregnancy occurred in 0.6% of the women (95% CI 0.01-1.6%; I2 = 79%; 39 studies; 1166 women).

WIDER IMPLICATIONS

Our study found no indication that SARS-CoV-2 infection in the first or second trimester increases the risk of miscarriages. To provide better risk estimates, well-designed studies are needed that include pregnant women with and without SARS-CoV-2 infection at conception and early pregnancy and consider the association of clinical manifestation and severity of SARS-CoV-2 infection with pregnancy loss, as well as potential confounding factors such as previous pregnancy loss. For clinical practice, pregnant women should still be advised to take precautions to avoid risk of SARS-CoV-2 exposure and receive SARS-CoV-2 vaccination.

Gestational diabetes mellitus in the era of COVID-19: Challenges and opportunities

BACKGROUND AND AIMS

The impact of the coronavirus disease 2019 (COVID-19) pandemic on pregnant women, especially those with gestational diabetes mellitus (GDM), has yet to be fully understood. This review aims to examine the interaction between GDM and COVID-19 and to elucidate the pathophysiological mechanisms underlying the comorbidity of these two conditions.

METHODS

We performed a systematic literature search using the databases of PubMed, Embase, and Web of Science with appropriate keywords and MeSH terms. Our analysis included studies published up to January 26, 2023.

RESULTS

Despite distinct clinical manifestations, GDM and COVID-19 share common pathophysiological characteristics, which involve complex interactions across multiple organs and systems. On the one hand, infection with severe acute respiratory syndrome coronavirus 2 may target the pancreas and placenta, resulting in β-cell dysfunction and insulin resistance in pregnant women. On the other hand, the hormonal and inflammatory changes that occur during pregnancy could also increase the risk of severe COVID-19 in mothers with GDM. Personalized management and close monitoring are crucial for treating pregnant women with both GDM and COVID-19.

CONCLUSIONS

A comprehensive understanding of the interactive mechanisms of GDM and COVID-19 would facilitate the initiation of more targeted preventive and therapeutic strategies. There is an urgent need to develop novel biomarkers and functional indicators for early identification and intervention of these conditions.

Unravelling the impact of COVID-19 on pregnancy: In aspect of placental histopathology and umbilical cord macrophage immunoactivity with neonatal outcomes

COVID-19 has turned into a global pandemic since it was first detected in 2019, causing serious public health problems. Our objective was to investigate the impact of COVID-19 on pregnant women and newborns, who belong to the vulnerable segments of society. Our study involved the histopathological examination of placentas and umbilical cords from two groups of pregnant women. Group I consisted of pregnant women who had never tested positive for COVID-19 during their pregnancy (n: 20). Group II consisted of pregnant women who had contracted COVID-19, exhibited moderate and mild symptoms, and recovered from the disease before giving birth (n: 23). Furthermore, we employed immunofluorescence techniques to detect macrophage activity in the umbilical cord. Prenatal assessments were based on maternal complete blood counts and coagulation assays (n:40 in both groups). Newborn conditions were evaluated using birth weight, height, head circumference, and APGAR (n:40 in both groups). Our analyses reveal that COVID-19 causes placental and umbilical cord inflammation and maternal and foetal vascular malperfussion. Our immunofluorescence investigations demonstrate a notable increase in macrophage numbers and the macrophage-to-total cell ratio within the COVID-19 group. In this aspect, this study provides the initial report incorporating macrophage activity results from Warton's jelly in pregnants who have recovered from COVID-19. We have also ascertained that COVID-19 abbreviates gestation periods and concurrently diminishes maternal haemoglobin concentrations. Consequently, COVID-19 with mild and moderate symptoms during pregnancy, causes significant changes to the placenta and umbilical cord, but propitiously does not cause a significant difference in the neonatal outcomes.

Management of COVID-19-Associated Acute Respiratory Distress Syndrome (ARDS) During Pregnancy Following In Vitro Fertilization (IVF)

Coronavirus disease 2019 (COVID-19), the disease caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is recognized for its heterogeneous clinical presentation, complex pathophysiology, and broad spectrum of manifestations. Obstetric patients have been a subject of considerable interest due to their potential vulnerability to more severe infection and adverse pregnancy outcomes, exemplified by this report of a 43-year-old pregnant female with severe COVID-19 infection and respiratory complications. This case report aims to contribute to the existing scientific knowledge by presenting a detailed clinical profile of a patient with COVID-19 who achieved pregnancy through in vitro fertilization (IVF) and discussing the management and outcomes of the infection. The neonate's negative COVID-19 tests suggest no intrauterine transmission; prompt medical interventions, including mechanical ventilation and targeted antibiotic therapy, were implemented to stabilize her condition. Close collaboration among the multidisciplinary team and careful monitoring of vital functions and laboratory parameters were crucial in managing the patient's complex condition. Thus, this case highlights the importance of a comprehensive and multidisciplinary approach in managing severe COVID-19 cases in pregnancy, emphasizing the need for prompt recognition of complications and timely intervention.

COVID-19, Pregnancy, and Diabetes Mellitus

During the severe acute respiratory distress virus coronavirus type 2 (SARS-CoV-2) pandemic, many women were infected during their pregnancies. The SARS-CoV-2-induced coronavirus disease 19 (COVID-19) has an impact on maternal health and pregnancy outcomes; peripartum and perinatal morbidity and mortality are increased. Pregnancy is considered a risk factor for severe COVID-19 course. Additional risk factors during pregnancy are diabetes mellitus, gestational diabetes mellitus (GDM), and obesity. Systemic inflammation can lead to severe metabolic dysregulation with ketoacidosis. The endocrine pancreas is a target organ for SARS-CoV-2 and the fetal risk depends on inflammation of the placenta. Up to now there is no evidence that SARS-CoV-2 infection during pregnancy leads to permanent diabetes in mothers or their offspring via triggering autoimmunity or beta cell destruction. The frequently observed increased prevalence of GDM compared to the years before the pandemic is most likely due to changed lifestyle during lockdown. Furthermore, severe COVID-19 may be associated with the development of GDM due to worsening of glucose tolerance. Vaccination with a mRNA vaccine is safe and highly effective to prevent infection and to reduce hospitalization. Registries support offering evidence-based recommendations on vaccination for pregnant women. Even with the current omicron virus variant, there are increased risks for symptomatic and unvaccinated pregnant women.

Pregnancy and infant outcomes following SARS-CoV-2 infection in pregnancy during delta variant predominance - Surveillance for Emerging Threats to Pregnant People and Infants

BACKGROUND

SARS-CoV-2 infection in pregnancy is associated with an increased risk of adverse birth outcomes such as preterm birth, stillbirth, and maternal and infant complications. Previous research suggests an increased risk of severe COVID-19 illness and stillbirth in pregnant people during delta variant predominance in 2021; however, those studies did not assess timing of infection during pregnancy, and few of them described COVID-19 vaccination status.

OBJECTIVE

Using a large population-based cohort, this study compared pregnancy and infant outcomes and described demographic and clinical characteristics of pregnant people with SARS-CoV-2 infection prior to and during the delta variant period.

STUDY DESIGN

This retrospective cohort analysis included persons with confirmed SARS-CoV-2 infection in pregnancy from 6 US jurisdictions reporting to the Surveillance for Emerging Threats to Pregnant People and Infants Network. Data were collected through case reports of polymerase chain reaction-positive pregnant persons and linkages to birth certificates, fetal death records, and immunization records. We described clinical characteristics and compared frequency of spontaneous abortion (<20 weeks of gestation), stillbirth (≥20 weeks), preterm birth (<37 weeks), small for gestational age, and term infant neonatal intensive care unit admission between the time periods of pre-delta and delta variant predominance. Study time periods were determined by when variants constituted more than 50% of sequences isolated according to regional SARS-CoV-2 genomic surveillance data, with time periods defined for pre-delta (March 3, 2020-June 25, 2021) and Delta (June 26, 2021-December 25, 2021). Adjusted prevalence ratios were estimated for each outcome measure using Poisson regression and were adjusted for continuous maternal age, race and ethnicity, and insurance status at delivery.

RESULTS

Among 57,563 pregnancy outcomes, 57,188 (99.3%) were liveborn infants, 65 (0.1%) were spontaneous abortions, and 310 (0.5%) were stillbirths. Most pregnant persons were unvaccinated at the time of SARS-CoV-2 infection, with a higher proportion in pre-delta (99.4%) than in the delta period (78.4%). Of those with infections during delta and who were previously vaccinated, the timing from last vaccination to infection was a median of 183 days. Compared to pre-delta, infections during delta were associated with a higher frequency of stillbirths (0.7% vs 0.4%; adjusted prevalence ratio, 1.55; 95% confidence interval, 1.14-2.09) and preterm births (12.8% vs 11.9%; adjusted prevalence ratio, 1.14; 95% confidence interval, 1.07-1.20). The delta period was associated with a lower frequency of neonatal intensive care unit admission (adjusted prevalence ratio, 0.74; 95% confidence interval, 0.67-0.82) than in the pre-delta period. During the delta period, infection during the third trimester was associated with a higher frequency of preterm birth (adjusted prevalence ratio, 1.41; 95% confidence interval, 1.28-1.56) and neonatal intensive care unit admission (adjusted prevalence ratio, 1.21; 95% confidence interval, 1.01-1.45) compared to the first and second trimester combined.

CONCLUSION

In this US-based cohort of persons with SARS-CoV-2 infection in pregnancy, the majority were unvaccinated, and frequencies of stillbirth and preterm birth were higher during the delta variant predominance period than in the pre-delta period. During the delta period, frequency of preterm birth and neonatal intensive care unit admission was higher among infections occurring in the third trimester vs those earlier in pregnancy. These findings demonstrate population-level increases of adverse fetal and infant outcomes, specifically in the presence of a COVID-19 variant with more severe presentation.

Stillbirth risk factors, causes and evaluation

Stillbirth impacts 5.73 per 1,000 births in the United States and this rate exceeds that of contemporary high-resource countries.1,2 Risk factors include both demographic and medical characteristics. There are also numerous pathophysiologic mechanisms that can lead to stillbirth. Unfortunately, these risk factors are fairly common, making stillbirth risk stratification and prevention challenging. This is due in part to a large number of unexplained stillbirths. In a large, multi-center study of stillbirths, approximately 24% of stillbirths remained unexplained following thorough, standardized evaluation.3 The number of unexplained stillbirths is unquestionably larger outside of a rigorous study protocol, but real-world data are lacking. This large proportion of unexplained stillbirth cases makes achieving further decreases in the stillbirth rate difficult given lack of understanding of underlying causes in this population. Cause of death identification can be improved with adoption of an evidence-based, comprehensive stillbirth evaluation.

Extracorporeal Membrane Oxygenation in Pregnant and Postpartum Women With Critical Coronavirus Disease 2019 (COVID-19) Acute Respiratory Distress Syndrome: A Systematic Review and Meta-analysis

OBJECTIVE

To estimate the maternal survival and live-birth rates in pregnant women with acute respiratory distress syndrome (ARDS) secondary to critical coronavirus disease 2019 (COVID-19) who are treated with extracorporeal membrane oxygenation (ECMO) by performing a systematic review and meta-analysis.

DATA SOURCES

From database inception through August 2023, we explored MEDLINE, Web of Science, EMBASE, CINAHL, ClinicalTrials.gov, and Cochrane Central Register of Controlled Trials. Studies reporting maternal survival and live-birth rates in pregnant women with critical COVID-19 undergoing ECMO were included.

METHODS OF STUDY SELECTION

Two reviewers separately ascertained studies, obtained data, and evaluated study quality. Summary estimates of maternal survival and live-birth rates were measured, and 95% CIs were calculated.

TABULATION, INTEGRATION, AND RESULTS

Nine retrospective case series and 12 retrospective cohort studies were identified with 386 pregnant women with critical COVID-19 who underwent ECMO. Studies evaluated women that were treated from January 2020 to October 2022. Four studies were from the United States; three were from Turkey; two were from France; two were from Israel; and one each was from Columbia, Germany, Italy, Kuwait, Poland, Republic of Srpska, the United Arab Emirates, the United Kingdom, a consortium from Belgium, France, Switzerland, and an international registry. The pooled estimate of the maternal survival rate among pregnant patients who were initiated on ECMO was 75.6% (95% CI, 66.0-84.1%, I2 =72%). The pooled estimate of the live-birth rate among pregnant patients who were initiated on ECMO was 83.7% (95% CI, 76.8-89.6%, 153 neonates, I2 =11%). When the case series and cohort studies were examined separately, the results were similar.

CONCLUSION

Among pregnant women with acute respiratory distress syndrome attributable to critical COVID-19 who were managed with ECMO, maternal survival and live-birth rates were high.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42023442800.

Adverse perinatal outcomes in gestational diabetes mellitus with and without SARS-CoV-2 infection during pregnancy: results from two nationwide registries in Germany

INTRODUCTION

Pregnancy is a known independent risk factor for a severe course of COVID-19. The relationship of SARS-CoV-2 infection and gestational diabetes mellitus (GDM) on neonatal outcomes is unclear. Our aim was to determine if SARS-CoV-2 infection represents an independent risk factor for adverse perinatal outcomes in pregnancy with GDM.

RESEARCH DESIGN AND METHODS

We compared data from two German registries including pregnant women with GDM, established during the SARS-CoV-2 pandemic (COVID-19-Related Obstetric and Neonatal Outcome Study (CRONOS), a multicenter prospective observational study) and already existing before the pandemic (German registry of pregnant women with GDM; GestDiab). In total, 409 participants with GDM and SARS-CoV-2 infection and 4598 participants with GDM, registered 2018-2019, were eligible for analyses. The primary fetal and neonatal outcomes were defined as: (1) combined: admission to neonatal intensive care unit, stillbirth, and/or neonatal death, and (2) preterm birth before 37+0 weeks of gestation. Large and small for gestational age, maternal insulin therapy, birth weight >4500 g and cesarean delivery were considered as secondary outcomes.

RESULTS

Women with SARS-CoV-2 infection were younger (32 vs 33 years) and had a higher median body mass index (28 vs 27 kg/m²). In CRONOS, more neonates developed the primary outcome (adjusted OR (aOR) 1.48, 95% CI 1.11 to 1.97) and were born preterm (aOR 1.50, 95% CI 1.07 to 2.10). Fasting glucose was higher in women in CRONOS versus GestDiab (5.4 vs 5.3 mmol/L) considering each 0.1 mmol/L increase was independently associated with a 5% higher risk of preterm birth among women in CRONOS only (aOR 1.05, 95% CI 1.01 to 1.09).

CONCLUSIONS

GDM with SARS-CoV-2 infection in pregnancy is associated with an increased risk of adverse fetal and neonatal outcomes as compared with GDM without SARS-CoV-2 infection.

Clinical Characteristics and Risk of Hypoxemia Development in Women Infected with SARS-CoV-2 during Pregnancy

PURPOSE

There is limited information on the clinical characteristics and prognosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during pregnancy. The clinical features and risk factors for hypoxemia development were investigated in pregnant women with coronavirus disease-2019 (COVID-19).

MATERIALS AND METHODS

From August 2020 to February 2022, we performed a retrospective cohort study of 410 pregnant women with COVID-19. The clinical characteristics and prognoses were compared between pregnant COVID-19 patients requiring oxygen and those who did not.

RESULTS

Of 410 patients, 100 (24.4%) required oxygen therapy. Among them, fever [163 (52.6%) vs. 81 (81.0%), p<0.001] and cough [172 (56.4%) vs. 73 (73.0%), p=0.003] were more frequently observed than in non-oxygen group. The proportion of unvaccinated women was higher in oxygen group than in non-oxygen group [264 (85.2%) vs. 98 (98.0%), p=0.003]. During the Omicron wave, patients were more likely to have no oxygen requirement [98 (31.6%) vs. 18 (18.0%), p=0.009]. The risk of hypoxemic respiratory difficulty increased if SARS-CoV-2 infection occurred during the third trimester [adjusted odds ratio (aOR) 5.083, 95% confidence interval (CI): 1.095-23.593, p=0.038] and C-reactive protein (CRP) was elevated (≥1.0 mg/dL) at admission (aOR 5.878, 95% CI: 3.099-11.146, p<0.001). The risk was higher in unvaccinated patients (aOR 5.376, 95% CI: 1.193-24.390, p=0.028). However, the risk was lower in patients during the Omicron wave (aOR 0.498, 95% CI: 0.258-0.961, p=0.038).

CONCLUSION

A quarter of SARS-CoV-2-infected women developed hypoxemic respiratory difficulty during pregnancy. SARS-CoV-2 infection during the third trimester, CRP elevation at admission, and no vaccination increased the risk of hypoxemia in pregnant women.