Pregnancy outcomes and vaccine effectiveness during the period of omicron as the variant of concern, INTERCOVID-2022: a multinational, observational study

Efficacy of vaccination during pregnancy in reducing the risk of SARS-CoV-2 infection in infants younger than 12 months. Puglia (Italy), 2021-23

This retrospective cohort study evaluated the effectiveness of maternal vaccination against COVID-19 in reducing the risk of SARS-CoV-2 infection in infants younger than 12 months. The study, conducted at the "Policlinico" University Hospital of Bari, included 3346 newborns and their mothers. The study explored the degree of protection offered by maternal vaccination depending on the timing, type, and trimester of vaccination, also taking into account the mother's history of infection. We compared the incidence rate of infection between children of vaccinated and unvaccinated mothers; the values were 10.2% and 18.1%, respectively, and the difference was statistically significant. The overall effectiveness of the vaccine against the infection was 45%. Further analysis revealed increasing efficacy as the doses of vaccine administered to the mother increased and in case of a previous history of maternal infection. Dual immune stimulation (vaccination and natural infection) was 83% effective in preventing infection among newborns. The multivariable models confirmed the protective effect of vaccination with all types of vaccines used. The analysis of infection's incidence in newborns revealed an interesting temporal trend, with increasing incidence with time, suggesting a possible correlation with the persistence of maternal antibodies or with the gradual weaning. The results on the protective capacity of vaccines are in line with the global literature. Strengths of study include sample size, robust methodology, and multivariate analyses. Institutions could intensify awareness campaigns to encourage both pregnant women and all those who would like to become pregnant to receive SARS-CoV-2 vaccination.

Maternal and neonatal outcomes and clinical laboratory testing of pregnant women with COVID-19 during the BA.5.2/BF.7 surge

The impact of COVID-19 on pregnant women and newborns continues to be a critical societal concern. However, the majority of research focuses on the disease resulting from the early pandemic variants, without sufficient study on the more recent BA.5.2/BF.7. We retrospectively recruited pregnant women giving birth during the surge of the BA.5.2/BF.7 and analysed the risk impact of COVID-19 on maternal and neonatal outcomes. Furthermore, subjects matched through propensity scores were used for the analysis of clinical laboratory tests. A total of 818 pregnant women were enrolled, among 276 (33.7%) were diagnosed with SARS-CoV-2 during childbirth. COVID-19 significantly increased the risk of a hospital length of stay equal to or greater than seven days and neonatal admission to the neonatal intensive care unit, with an aHR of 2.03 (95% CI, 1.22-3.38) and 1.51 (95% CI, 1.12-2.03), respectively. In the analysis of 462 matched subjects, it was found that subjects infected with SARS-CoV-2 tended slight leucopenia and coagulation abnormalities. We found that during the surge of the BA.5.2/BF.7, COVID-19 increased the risk of maternal and neonatal outcomes among Chinese pregnant women. This finding offers significant insights to guide clinical practices involving pregnant women infected with the recently emerged Omicron subvariants.

Safety and Effectiveness of COVID-19 Vaccines During Pregnancy: A Living Systematic Review and Meta-analysis

BACKGROUND

Pregnant persons are susceptible to significant complications following COVID-19, even death. However, worldwide COVID-19 vaccination coverage during pregnancy remains suboptimal.

OBJECTIVE

This study assessed the safety and effectiveness of COVID-19 vaccines administered to pregnant persons and shared this evidence via an interactive online website.

METHODS

We followed Cochrane methods to conduct this living systematic review. We included studies assessing the effects of COVID-19 vaccines in pregnant persons. We conducted searches every other week for studies until October 2023, without restrictions on language or publication status, in ten databases, guidelines, preprint servers, and COVID-19 websites. The reference lists of eligible studies were hand searched to identify additional relevant studies. Pairs of review authors independently selected eligible studies using the web-based software COVIDENCE. Data extraction and risk of bias assessment were performed independently by pairs of authors. Disagreements were resolved by consensus. We performed random-effects meta-analyses of adjusted relative effects for relevant confounders of comparative studies and proportional meta-analyses to summarize frequencies from one-sample studies using R statistical software. We present the GRADE certainty of evidence from comparative studies. Findings are available on an interactive living systematic review webpage, including an updated evidence map and real-time meta-analyses customizable by subgroups and filters.

RESULTS

We included 177 studies involving 638,791 participants from 41 countries. Among the 11 types of COVID-19 vaccines identified, the most frequently used platforms were mRNA (154 studies), viral vector (51), and inactivated virus vaccines (17). Low to very low-certainty evidence suggests that vaccination may result in minimal to no important differences compared to no vaccination in all assessed maternal and infant safety outcomes from 26 fewer to 17 more events per 1000 pregnant persons, and 13 fewer to 9 more events per 1000 neonates, respectively. We found statistically significant reductions in emergency cesarean deliveries (9%) with mRNA vaccines, and in stillbirth (75-83%) with mRNA/viral vector vaccines. Low to very low-certainty evidence suggests that vaccination during pregnancy with mRNA vaccines may reduce severe cases or hospitalizations in pregnant persons with COVID-19 (72%; 95% confidence interval [CI] 42-86), symptomatic COVID-19 (78%; 95% CI 21-94), and virologically confirmed SARS-CoV-2 infection (82%; 95% CI 39-95). Reductions were lower with other vaccine types and during Omicron variant dominance than Alpha and Delta dominance. Infants also presented with fewer severe cases or hospitalizations due to COVID-19 and laboratory-confirmed SARS-CoV-2 infection (64%; 95% CI 37-80 and 66%; 95% CI 37-81, respectively).

CONCLUSIONS

We found a large body of evidence supporting the safety and effectiveness of COVID-19 vaccines during pregnancy. While the certainty of evidence is not high, it stands as the most reliable option available, given the current absence of pregnant individuals in clinical trials. Results are shared in near real time in an accessible and interactive format for scientists, decision makers, clinicians, and the general public. This living systematic review highlights the relevance of continuous vaccine safety and effectiveness monitoring, particularly in at-risk populations for COVID-19 impact such as pregnant persons, during the introduction of new vaccines.

CLINICAL TRIAL REGISTRATION

PROSPERO: CRD42021281290.

Maternal vaccination against COVID-19 and neonatal outcomes during Omicron: INTERCOVID-2022 study

BACKGROUND

In early 2023, when Omicron was the variant of concern, we showed that vaccinating pregnant women decreased the risk for severe COVID-19-related complications and maternal morbidity and mortality.

OBJECTIVE

This study aimed to analyze the impact of COVID-19 during pregnancy on newborns and the effects of maternal COVID-19 vaccination on neonatal outcomes when Omicron was the variant of concern.

STUDY DESIGN

INTERCOVID-2022 was a large, prospective, observational study, conducted in 40 hospitals across 18 countries, from November 27, 2021 (the day after the World Health Organization declared Omicron the variant of concern) to June 30, 2022, to assess the effect of COVID-19 in pregnancy on maternal and neonatal outcomes and to assess vaccine effectiveness. Women diagnosed with laboratory-confirmed COVID-19 during pregnancy were compared with 2 nondiagnosed, unmatched women recruited concomitantly and consecutively during pregnancy or at delivery. Mother-newborn dyads were followed until hospital discharge. The primary outcomes were a neonatal positive test for COVID-19, severe neonatal morbidity index, severe perinatal morbidity and mortality index, preterm birth, neonatal death, referral to neonatal intensive care unit, and diseases during the neonatal period. Vaccine effectiveness was estimated with adjustment for maternal risk profile.

RESULTS

We enrolled 4707 neonates born to 1577 (33.5%) mothers diagnosed with COVID-19 and 3130 (66.5%) nondiagnosed mothers. Among the diagnosed mothers, 642 (40.7%) were not vaccinated, 147 (9.3%) were partially vaccinated, 551 (34.9%) were completely vaccinated, and 237 (15.0%) also had a booster vaccine. Neonates of booster-vaccinated mothers had less than half (relative risk, 0.46; 95% confidence interval, 0.23-0.91) the risk of being diagnosed with COVID-19 when compared with those of unvaccinated mothers; they also had the lowest rates of preterm birth, medically indicated preterm birth, respiratory distress syndrome, and number of days in the neonatal intensive care unit. Newborns of unvaccinated mothers had double the risk for neonatal death (relative risk, 2.06; 95% confidence interval, 1.06-4.00) when compared with those of nondiagnosed mothers. Vaccination was not associated with any congenital malformations. Although all vaccines provided protection against neonatal test positivity, newborns of booster-vaccinated mothers had the highest vaccine effectiveness (64%; 95% confidence interval, 10%-86%). Vaccine effectiveness was not as high for messenger RNA vaccines only. Vaccine effectiveness against moderate or severe neonatal outcomes was much lower, namely 13% in the booster-vaccinated group (all vaccines) and 25% and 28% in the completely and booster-vaccinated groups, respectively (messenger RNA vaccines only). Vaccines were fairly effective in protecting neonates when given to pregnant women ≤100 days (14 weeks) before birth; thereafter, the risk increased and was much higher after 200 days (29 weeks). Finally, none of the neonatal practices studied, including skin-to-skin contact and direct breastfeeding, increased the risk for infecting newborns.

CONCLUSION

When Omicron was the variant of concern, newborns of unvaccinated mothers had an increased risk for neonatal death. Neonates of vaccinated mothers had a decreased risk for preterm birth and adverse neonatal outcomes. Because the protective effect of COVID-19 vaccination decreases with time, to ensure that newborns are maximally protected against COVID-19, mothers should receive a vaccine or booster dose no more than 14 weeks before the expected date of delivery.

COVID-19 diagnosis, vaccination during pregnancy, and adverse pregnancy outcomes of 865,654 women in England and Wales: a population-based cohort study

Background

The extent to which COVID-19 diagnosis and vaccination during pregnancy are associated with risks of common and rare adverse pregnancy outcomes remains uncertain. We compared the incidence of adverse pregnancy outcomes in women with and without COVID-19 diagnosis and vaccination during pregnancy.

Methods

We studied population-scale linked electronic health records for women with singleton pregnancies in England and Wales from 1 August 2019 to 31 December 2021. This time period was divided at 8th December 2020 into pre-vaccination and vaccination roll-out eras. We calculated adjusted hazard ratios (HRs) for common and rare pregnancy outcomes according to the time since COVID-19 diagnosis and vaccination and by pregnancy trimester and COVID-19 variant.

Findings

Amongst 865,654 pregnant women, we recorded 60,134 (7%) COVID-19 diagnoses and 182,120 (21%) adverse pregnancy outcomes. COVID-19 diagnosis was associated with a higher risk of gestational diabetes (adjusted HR 1.22, 95% CI 1.18-1.26), gestational hypertension (1.16, 1.10-1.22), pre-eclampsia (1.20, 1.12-1.28), preterm birth (1.63, 1.57-1.69, and 1.68, 1.61-1.75 for spontaneous preterm), very preterm birth (2.04, 1.86-2.23), small for gestational age (1.12, 1.07-1.18), thrombotic venous events (1.85, 1.56-2.20) and stillbirth (only within 14-days since COVID-19 diagnosis, 3.39, 2.23-5.15). HRs were more pronounced in the pre-vaccination era, within 14-days since COVID-19 diagnosis, when COVID-19 diagnosis occurred in the 3rd trimester, and in the original variant era. There was no evidence to suggest COVID-19 vaccination during pregnancy was associated with a higher risk of adverse pregnancy outcomes. Instead, dose 1 of COVID-19 vaccine was associated with lower risks of preterm birth (0.90, 0.86-0.95), very preterm birth (0.84, 0.76-0.94), small for gestational age (0.93, 0.88-0.99), and stillbirth (0.67, 0.49-0.92).

Interpretation

Pregnant women with a COVID-19 diagnosis have higher risks of adverse pregnancy outcomes. These findings support recommendations towards high-priority vaccination against COVID-19 in pregnant women.

Funding

BHF, ESRC, Forte, HDR-UK, MRC, NIHR and VR.

No impact of COVID-19 at delivery on maternal mortality or infant adverse birth outcomes in Botswana during the Omicron era

SARS-CoV-2 infection during pregnancy was associated with maternal mortality and adverse birth outcomes in the pre-Omicron era, including a stillbirth rate of 5.6% in Botswana. We re-evaluated these outcomes in the Tsepamo Study during the Omicron era. We assessed maternal mortality and adverse birth outcomes for all singleton pregnancies from mid-November 2021 (the start of the Omicron era) to mid-August 2022 at nine Tsepamo sites, among individuals with documented SARS-CoV-2 screening PCR or antigen tests and known HIV status. Of 9,705 women routinely screened for SARS-CoV-2 infection at delivery (64% of deliveries at these sites), 373 (3.8%) tested positive. Women with HIV were as likely to test positive for SARS-CoV-2 (77/1833, 4.2%) as women without HIV (293/6981, 4.2%) (p = 1.0). There were 5 recorded maternal deaths (0.03%), one occurring in a woman with a positive SARS-CoV-2 test result. In contrast, maternal mortality was 3.7% and 0.1% in those with and without SARS-CoV-2, respectively, during the pre-Omicron era. In the Omicron era, there were no differences among infants exposed or unexposed to SARS-CoV-2 in overall adverse birth outcomes (28.1% vs 29.6%; aRR 1.0, 95%CI 0.8-1.1), severe adverse birth outcomes (11.9 vs 10.6%; aRR 1.1, 95%CI 0.8-1.5), preterm delivery (15.1% vs 14.9%; aRR 1.0, 95%CI 0.8-1.3), or stillbirth (1.9% vs 2.3%; aRR 0.8, 95%CI 0.4-1.7). Adverse outcomes among those exposed to both HIV and SARS-CoV-2 were similar to those exposed to HIV alone (31.2% vs. 33.1%; aRR 0.9, 95%CI 0.6-1.3; p = 0.5). Maternal mortality was far lower in Botswana during the Omicron era than in the pre-Omicron era, and adverse birth outcomes were no longer significantly impacted by exposure to SARS-CoV-2 either overall or with HIV co-exposure. Increased population immunity to SARS-CoV-2, less stress on the hospital systems in the Omicron era, and possible differences in viral pathogenicity may combine to explain these findings.

Effect of omicron infection on maternal and neonatal delivery outcomes: A retrospective cohort study

BACKGROUND

People are very concerned about the adverse effects of Omicron infection on delivery modes, duration of labor, and the postpartum status of pregnant women and neonates.

METHODS

382 pregnant women (Omicron group: 136 cases; non-Omicron group: 246 cases) giving birth in our hospital were collected, demographic characteristics, vaccination, clinical manifestation and medication, delivery outcomes of pregnant women and neonates were recorded. Delivery outcomes were compared between the Omicron and non-Omicron groups, acute infection and non-acute infection groups to explore the relationship between adverse delivery outcomes and Omicron infection.

RESULTS

Pregnant women in the Omicron group had a longer hospitalization time (6.3 ± 3.6 days vs.5.5 ± 2.3 days), more 2-hour postpartum hemorrhage (291.7 ± 104.9 mL vs.262.7 ± 91.2 mL) and higher neonatal-pediatric transfer rate (20.6 % vs. 2.8 %), which might be associated with fetal distress, prenatal fever and pneumonia/respiratory distress. Neonates transferred to pediatrics due to jaundice were unique in the Omicron group. Fever-pregnant women have a more prolonged second stage of labor and hospital stay while coughing or expectoration ones have a shorter third stage of labor. Delivery outcomes did not differ whether the infected pregnant women were in the acute phase and whether to use antipyretics.

CONCLUSION

Omicron infection can increase the 2-hour postpartum hemorrhage volume and the neonatal-pediatric transfer rate. The symptoms can affect the duration of labor and hospital stay. However, whether the infected pregnant women are in the acute phase or use antipyretics do not affect the delivery outcome.

Prevalence and factors influencing long COVID among primary healthcare workers after epidemic control policy adjustment in Jiangsu, China

OBJECTIVE

The persistent symptoms arising from COVID-19 infection pose a substantial threat to patients' health, carrying significant implications. Amidst the evolving COVID-19 control strategies in China, healthcare workers (HCWs) endure considerable stress. This study aims to evaluate the prevalence of long COVID infections and their influencing factors among primary HCWs after epidemic control policy adjustment in Jiangsu.

METHODS

A self-designed questionnaire was administered through on-site surveys among primary HCWs in five counties and districts within Jiangsu Province from July 4 to July 20, 2023. Logistic regression analysis was employed to identify factors associated with long COVID.

RESULTS

The prevalence of long COVID among primary HCWs stood at 12.61%, with a 95% confidence interval (CI) of 11.67-13.55%. Among those affected, the most common long COVID symptoms were hypomnesia (4.90%, 95%CI: 4.29-5.51%), sleep difficulties (2.73%, 95%CI: 2.27-3.19%), fatigue (2.35%, 95%CI: 1.92-2.78%), disturbances in the reproductive system (1.93%, 95%CI: 1.54-2.32%), hair loss (1.85%, 95%CI: 1.47-2.23%), and myalgia/arthralgia (1.51%, 95%CI: 1.16-1.86%). Multivariate logistic regression revealed that older age groups (30-45 years (adjusted odds ratio (aOR) = 1.93, 95%CI: 1.44-2.58), 45-60 years (aOR = 2.82, 95%CI: 2.07-3.84)), females (aOR = 1.26, 95%CI: 1.03-1.55), and higher work stress (high stress (aOR = 1.52, 95%CI: 1.24-1.86), extremely high stress (aOR = 1.37, 95%CI: 1.03-1.82)) were more prone to long COVID. Conversely, individuals with educational attainment below the bachelor's degree (aOR = 0.67, 95%CI: 0.55-0.82) and those who received four or more doses of the COVID-19 vaccine (aOR = 0.55, 95%CI: 0.33-0.92) were at a reduced risk.

CONCLUSION

This study investigates the prevalence of long COVID among primary HCWs and identifies key influencing factors. These findings are crucial for assisting in the early identification of COVID-19 patients at risk for long-term complications, developing targeted interventions aimed at optimizing healthcare resource allocation and enhancing the work conditions and quality of life of HCWs. To mitigate the prevalence of long COVID, healthcare providers and local authorities should implement effective measures, such as optimizing work-rest schedules and actively advocating for vaccination.

Preventing Postpartum Venous Thromboembolism With Low-Molecular-Weight Heparin: The PP-HEP Pilot Randomised Controlled Trial

OBJECTIVE

Uncertainty surrounds the risk-benefit of low-molecular-weight heparin to prevent postpartum venous thromboembolism (VTE). Data from randomised clinical trials (RCT) are critically needed, but recent feasibility studies in North America yielded low participation rates, with <1 enrolment per month per centre. Our aim was to assess the feasibility of a trial of postpartum short-term enoxaparin in Europe.

DESIGN

Pragmatic, open-label pilot randomised controlled trial (RCT).

SETTING

Swiss tertiary hospital.

POPULATION

Postpartum women, within 48 h of delivery, deemed at intermediate risk of VTE with at least one major risk factor (morbid obesity, thrombophilia, emergency caesarean section, pre-eclampsia, preterm delivery, intrauterine growth restriction or systemic peripartum infection) and/or at least two minor risk factors.

METHODS

Participants were randomised to enoxaparin 40-60 mg once daily for 10 days or no treatment, with a 90-day follow-up.

MAIN OUTCOME MEASURES

Participation rate and study acceptance (randomised participants among women in whom informed consent was sought).

RESULTS

Recruitment was open for 25 weeks in 2022. Among 1504 postpartum women, 480 were eligible and 77 were randomised. The recruitment rate was 3.1 per week (13.3 per month) and the study acceptance was 23.8%. At 3 months, there was no VTE event, but one major, one nonmajor obstetrical bleeding and one surgical site complication, all in the enoxaparin group.

CONCLUSIONS

This pilot RCT of postpartum thromboprophylaxis set in Switzerland yielded greater participation rate and acceptance than previous attempts in North America. It calls for a large, international, collaborative trial to guide this important clinical decision.

TRIAL REGISTRATION

ClinicalTrial.gov identifier: NCT05878899 and NCT04153760.

COVID-19 vaccination before or during pregnancy results in high, sustained maternal neutralizing activity to SARS-CoV-2 wild-type and Delta/Omicron variants of concern, particularly following a booster dose or infection

OBJECTIVES

To investigate multi-dose and timings of COVID-19 vaccines in preventing antenatal infection.

DESIGN

Prospective observational study investigating primary vaccinations, boosters, antenatal COVID-19 infections, neutralizing antibody (Nab) durability, and cross-reactivity to Delta and Omicron variants of concern (VOCs).

RESULTS

Ninety-eight patients completed primary vaccination prepregnancy (29.6%) and antenatally (63.3%), 24.2% of whom had antenatal COVID-19, while 7.1% were unvaccinated (28.6% had antenatal COVID-19). None had severe COVID-19. Prepregnancy vaccination resulted in vaccination-to-infection delay of 23.3 weeks, which extended to 45.2 weeks with a booster, compared to 16.9 weeks following antenatal vaccination (P < 0.001). Infections occurred at 26.2 weeks gestation in women vaccinated prepregnancy compared to 36.2 weeks gestation in those vaccinated during pregnancy (P < 0.007). The risk of COVID-19 infection was higher without antenatal vaccination (hazard ratio [HR] 14.6, P = 0.05) and after prepregnancy vaccination without a booster (HR 10.4, P = 0.002). Antenatal vaccinations initially led to high Nab levels, with mild waning but subsequent rebound. Significant Nab enhancement occurred with a third-trimester booster. Maternal-neonatal Nab transfer was efficient (transfer ratio >1), and cross-reactivity to VOCs was observed.

CONCLUSION

Completing vaccination during any trimester delays COVID-19 infection and maintains effective neutralizing activity throughout pregnancy, with robust cross-reactivity to VOCs and efficient maternal-neonatal transfer.

Optimal Delivery Management for the Prevention of Early Neonatal SARS-CoV-2 Infection: Systematic Review and Meta-analysis

OBJECTIVE

 Delivery management interventions (DMIs) were recommended to prevent delivery-associated transmission of maternal SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) to infants without evidence of effect on early neonatal SARS-CoV-2 infection (ENI) and neonatal death <28 days of life (ND). This systematic review describes different DMI combinations and the frequency of ENI and ND.

STUDY DESIGN

 Individual patient data were collected from articles published from January 1, 2020 to December 31, 2021 from Cochrane review databases, Medline, and Google Scholar. Article inclusion criteria were: documented maternal SARS-CoV-2 polymerase chain reaction (PCR)-positive status 10 days before delivery or symptomatic at delivery with a positive test within 48 hours, known delivery method, and known infant SARS-CoV-2 PCR result. Primary outcomes were ENI (positive PCR at 12 hours to 10 days) and ND. All characteristics were pooled using the DerSimonian-Laird inverse variance method. Primary outcome analyses were performed using logit transformation and random effect. Pooled results were expressed as percentages (95% confidence intervals). Continuity correction was applied for all pooled results if any included study has 0 event.

RESULTS

 A total of 11,075 publications were screened. 117 publications representing 244 infants and 230 mothers were included. All publications were case reports. ENI and ND were reported in 23.4% (18.2-29.18) and 2.1% (0.67-4.72) of cases, respectively. Among cases with available information, DMIs were reported for physical environment (85-100%), delivery-specific interventions (47-100%), and infant care practices (80-100%). No significant comparisons could be performed between different DMI combinations due to small sample size.

CONCLUSION

 The evidence supporting any DMI in SARS-CoV-2-infected mothers to prevent ENI or ND is extremely limited. Limitations of this meta-analysis include high risk of bias, small sample size, and large confidence intervals. This identifies the need for multinational database generation and specific studies designed to provide evidence of DMI guidelines best suited to prevent transmission from mother to neonate.

KEY POINTS

· In this review we analyzed 2 years of maternal SARS-CoV-2 published cases.. · We assessed association of delivery management interventions with infant SARS-CoV-2 infection.. · We found no evidence supporting any DMI for that purpose..

Preserved prenatal lung growth assessed by fetal MRI in the omicron-dominated phase of the SARS-CoV-2 pandemic

OBJECTIVES

With SARS-CoV-2 evolving, disease severity and presentation have changed due to changes in mechanisms of entry and effector site as well as due to effects of vaccination- and/or infection-acquired immunity. We re-assessed fetal lung pathology in pregnancies with uncomplicated SARS-CoV-2 infections during the late, omicron-dominated pandemic phase to inform disease understanding and pregnancy consultation.

METHODS

In this case-control study, fetal lung volumes were assessed by fetal MRI in 24 pregnancies affected by mild maternal SARS-CoV-2 infection during the omicron-dominated pandemic phase with prevailing immunity through vaccination and/or prior SARS-CoV-2 infection.

RESULTS

Fetal lung volumes (normalized to estimated fetal weight) in 24 pregnancies (GA 33.3 ± 3.8, 12 female fetuses) following mild, uncomplicated SARS-CoV-2 infection did not differ significantly from both, published reference values (96.3% ± 22.5% of 50th percentile reference values, p = 0.43), or fetal lung volumes of a site-specific, non-COVID control group (n = 15, 94.2% ± 18.5%, p = 0.76). Placental assessment revealed no group differences in thrombotic changes or placental heterogeneity (p > 0.05, respectively), and fetal lung volume did not correlate with placental heterogeneity when adjusting for gestational age at scan (p > 0.05).

CONCLUSION

Assessment of fetal lung volume by MRI revealed unaffected lung growth in pregnancies affected by uncomplicated SARS-CoV-2 infection in the omicron-dominated pandemic phase in the presence of prevailing hybrid immunity. This finding contrasts sharply with the observed reduction in fetal lung volume following maternal alpha-variant infection in the pre-vaccination era and might reflect tropism- as well as immunity-related effects.

KEY POINTS

Question: Is fetal lung development affected by mild maternal SARS-CoV-2 infection during the omicron-dominated phase of the pandemic?

FINDINGS

Fetal lung volume in 24 affected pregnancies did not differ significantly from published reference values or fetal lung volumes in 15 site-specific, non-COVID-affected control pregnancies.

CLINICAL RELEVANCE

Preserved fetal lung volume following mild maternal SARS-CoV-2 infection during the omicron-dominated phase contrasts with previous findings of reduced volume in unvaccinated pregnancies during the alpha-dominated pandemic phase. These observations might reflect tropism- as well as immunity-related effects.

Maternal Immunization with Adjuvanted Recombinant Receptor-Binding Domain Protein Provides Immune Protection against SARS-CoV-2 in Infant Monkeys

Maternal vaccinations administered prior to conception or during pregnancy enhance the immune protection of newborn infants against many pathogens. A feasibility experiment was conducted to determine if monkeys can be used to model the placental transfer of maternal antibody against SARS-CoV-2. Six adult rhesus monkeys were immunized with adjuvanted recombinant-protein antigens comprised of receptor-binding domain human IgG1-Fc fusion proteins (RBD-Fc) containing protein sequences from the ancestral-Wuhan or Gamma variants. The female monkeys mounted robust and sustained anti-SARS-CoV-2 antibody responses. Blood samples collected from their infants after delivery verified prenatal transfer of high levels of spike-specific IgG, which were positively correlated with maternal IgG titers at term. In addition, an in vitro test of ACE2 neutralization indicated that the infants' IgG demonstrated antigen specificity, reflecting prior maternal immunization with either Wuhan or Gamma-variant antigens. All sera showed stronger ACE2-RBD binding inhibition when variants in the assay more closely resembled the vaccine RBD sequence than with more distantly related variants (i.e., Delta and Omicron). Monkeys are a valuable animal model for evaluating new vaccines that can promote maternal and infant health. Further, the findings highlight the enduring nature and safety of the immune protection elicited by an adjuvanted recombinant RBD-Fc vaccine.

COVID-19 Vaccination in the First Trimester and Major Structural Birth Defects Among Live Births

Importance

COVID-19 vaccination is recommended throughout pregnancy to prevent pregnancy complications and adverse birth outcomes associated with COVID-19 disease. To date, data on birth defects after first-trimester vaccination are limited.

Objective

To evaluate the associated risks for selected major structural birth defects among live-born infants after first-trimester receipt of a messenger RNA (mRNA) COVID-19 vaccine.

Design, Setting, and Participants

This was a retrospective cohort study of singleton pregnancies with estimated last menstrual period (LMP) between September 13, 2020, and April 3, 2021, and ending in live birth from March 5, 2021, to January 25, 2022. Included were data from 8 health systems in California, Oregon, Washington, Colorado, Minnesota, and Wisconsin in the Vaccine Safety Datalink.

Exposures

Receipt of 1 or 2 mRNA COVID-19 vaccine doses in the first trimester, as part of the primary series.

Main Outcomes and Measures

Selected major structural birth defects among live-born infants, identified from electronic health data using validated algorithms, with neural tube defects confirmed via medical record review.

Results

Among 42 156 eligible pregnancies (mean [SD] maternal age, 30.9 [5.0] years) 7632 (18.1%) received an mRNA COVID-19 vaccine in the first trimester. Of 34 524 pregnancies without a first-trimester COVID-19 vaccination, 2045 (5.9%) were vaccinated before pregnancy, 13 494 (39.1%) during the second or third trimester, and 18 985 (55.0%) were unvaccinated before or during pregnancy. Compared with pregnant people unvaccinated in the first trimester, those vaccinated in the first trimester were older (mean [SD] age, 32.3 [4.5] years vs 30.6 [5.1] years) and differed by LMP date. After applying stabilized inverse probability weighting, differences in baseline characteristics between vaccinated and unvaccinated pregnant persons in the first trimester were negligible (standardized mean difference <0.20). Selected major structural birth defects occurred in 113 infants (1.48%) after first-trimester mRNA COVID-19 vaccination and in 488 infants (1.41%) without first-trimester vaccine exposure; the adjusted prevalence ratio was 1.02 (95% CI, 0.78-1.33). In secondary analyses, with major structural birth defect outcomes grouped by organ system, no significant differences between infants vaccinated or unvaccinated in the first trimester were identified.

Conclusions and Relevance

In this multisite cohort study, among live-born infants, first-trimester mRNA COVID-19 vaccine exposure was not associated with an increased risk for selected major structural birth defects.

Pregnancy and perinatal outcomes of women with SARS-CoV-2 infection during pregnancy

INTRODUCTION

This study aimed to compare the pregnancy and perinatal outcomes of women with and without severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection during pregnancy.

METHODS

Women who delivered in an obstetric unit from March 2022 to October 2022 were recruited. The history of vaccination and SARS-CoV-2 infection during pregnancy was recorded. The pregnancy and perinatal outcomes of women with and without SARS-CoV-2 infection were compared.

RESULTS

A total of 1015 women were recruited - 41.5% had SARS-CoV-2 infection during pregnancy and 25.2% were unvaccinated. The incidences of preeclampsia, gestational diabetes mellitus and caesarean section were similar between the two groups. There were more preterm deliveries (9.0% vs 5.1%, P = 0.01) and more late preterm deliveries of between 33 and 36 + 6 weeks (6.2% vs. 3.7%, P = 0.03) in the SARS-CoV-2 infection group. There were no statistically significant differences between the two groups in perinatal outcomes, including birthweight, incidence of small for gestational age, low Apgar scores, and neonatal intensive care or special care baby unit admissions. There were no differences in pregnancy and perinatal outcomes between women infected in the first/second trimester and those infected in the third trimester, except for lower mean birthweight (3180 g vs. 3292 g, P = 0.04). There were no major differences in pregnancy outcome between vaccinated and unvaccinated women.

CONCLUSION

The pregnancy and perinatal outcomes of women who were infected with SARS-CoV-2 during gestation appear favourable.

Timing of maternal vaccination against COVID-19 for effective protection of neonates: cohort study

Introduction

Although the safety and effectiveness of COVID-19 vaccination during pregnancy have been proven, there is still little data explaining neonatal outcomes of maternal pre-pregnancy vaccination.

Methods

Here, we investigated the impact of vaccination and SARS-CoV-2 infection on maternal-neonate immune response in a cohort study involving 141 pregnant individuals, and defined the importance of maternal COVID-19 vaccination timing for its effectiveness.

Results and discussion

Our data indicate that vertically transferred maternal hybrid immunity provides significantly better antiviral protection for a neonate than either maternal post-infection or post-vaccination immunity alone. Higher neutralization potency among mothers immunized before pregnancy and their newborns highlights the promising role of pre-pregnancy vaccination in neonatal protection. A comparison of neutralizing antibody titers calculated for each dyad suggests that infection and pre-/during-pregnancy vaccination all support transplacental transfer, providing the offspring with strong passive immunity against SARS-CoV-2. Analysis of neutralizing antibody levels in maternal sera collected during pregnancy and later during delivery shows that immunization may exert a positive effect on maternal protection.

SARS-CoV-2 seroprevalence among Beninese pregnant women in the third year of the pandemic

BACKGROUND

Pregnant women are a vulnerable population to COVID-19 given an increased susceptibility to severe SARS-CoV-2 infection and pregnancy complications. However, few SARS-CoV-2 serological surveys have been performed among this population to assess the extent of the infection in sub-Saharan countries. The objectives of this study were to determine SARS-CoV-2 seroprevalence among Beninese pregnant women, to identify spatial seropositivity clusters and to analyse factors associated with the infection.

METHODS

A cross-sectional study including women in their third trimester of pregnancy attending the antenatal care (ANC) clinics at Allada (south Benin) and Natitingou (north Benin) was conducted. Rapid diagnostic tests (RDT) for detection of IgG/IgM against the SARS-CoV-2 spike protein were performed using capillary blood. Seroprevalence of SARS-CoV-2 antibodies and associations between SARS-CoV-2 serostatus and maternal characteristics were analyzed by multivariate logistic regression. Spatial analyses were performed using the spatial scan statistics to identify spatial clusters of SARS-CoV-2 infection.

RESULTS

A total of 861 pregnant women were enrolled between May 4 and June 29, 2022. 58/861 (6.7%) participants reported having received COVID-19 vaccine. None of the participants had been diagnosed with COVID-19 during their pregnancy. SARS-CoV-2 antibodies were detected in 607/802 (75.7%; 95% CI 72.56%-78.62%) of unvaccinated participants. Several urban and rural spatial clusters of SARS-CoV-2 cases were identified in Allada and one urban spatial cluster was identified in Natitingou. Unvaccinated participants from Allada with at least one previous morbidity were at a three-times higher risk of presenting SARS-CoV-2 antibodies (OR = 2.89; 95%CI 1.19%-7.00%).

CONCLUSION

Three out of four pregnant women had SARS-CoV-2 antibodies, suggesting a high virus circulation among pregnant women in Benin, while COVID-19 vaccination coverage was low. Pregnant women with comorbidities may be at increased risk of SARS-CoV-2 infection. This population should be prioritized for COVID-19 diagnosis and vaccination in order to prevent its deleterious effects.

TRIAL REGISTRATION

NCT06170320 (retrospectively registered on December 21, 2023).

What factors influence the uptake of vaccinations amongst pregnant women following the Covid-19 pandemic: A qualitative study

BACKGROUND

Pregnant women and their unborn babies are at increased risk from serious complications, hospitalisation and death from infectious diseases. Vaccinations for influenza (flu), pertussis (whooping cough) and Covid-19 are available for free for pregnant women in the UK, but uptake of these repeatedly remains low. This qualitative study aimed to explore how pregnant women feel about these vaccinations, and what factors influence the uptake of vaccinations amongst pregnant women since the onset of the Covid-19 pandemic.

METHODS

Pregnant women were recruited via two participating hospitals in one geographic area of the UK, and via one community group offering support to pregnant women from ethnic minorities. Semi-structured interviews were conducted remotely using telephone, were anonymised and transcribed, and analysed using thematic analysis.

FINDINGS

Interviews were conducted remotely with 43 pregnant women. The following themes were identified as influencing uptake of vaccinations amongst pregnant women: internal factors and beliefs, vaccination related factors, external influences and Covid-19 and changing perceptions of the pandemic.

DISCUSSION

Findings of this study increase awareness of some of the factors influencing vaccination decisions of pregnant women. It informs practice regarding healthcare professionals' discussions with pregnant women about vaccinations, and future vaccination campaigns and interventions that are targeting an increase in vaccination uptake amongst this population.

Knowledge, attitude and practice towards COVID-19 among pregnant women in Africa: A systematic review and meta-analysis

Background

Pregnant women and recent mothers face a higher risk of severe illness from Coronavirus disease 2019 due to physiological and immunological shifts during pregnancy, rendering them more vulnerable to inflammatory lung conditions. This susceptibility poses serious threats to both maternal and newborn health. Therefore, it is imperative for pregnant women to be fully informed about Coronavirus disease 2019 and to implement preventive measures. This study aimed to evaluate the collective knowledge, attitudes, and practices related to Coronavirus disease 2019 among pregnant women across Africa.

Methods

The researchers collected studies from multiple databases, including Pub Med/MEDLINE, EMBASE, CINAHL, Science Direct, Scopus, Web of Science, Cochran library, and Google Scholar. A combination of search terms and Boolean operators were utilized to gather relevant literature. Each study underwent quality assessment by five authors independently, using the modified Newcastle Ottawa Scale tailored for cross-sectional research. Statistical analysis was conducted using STATA™ Version 11 software, and meta-analysis was performed using the random-effects (Der Simonian and Laird) method. Heterogeneity was evaluated using I-squared (I2) statistics, and a one-out sensitivity analysis was carried out.

Results

This systematic review and meta-analysis included 19 articles, involving a total of 7852 participants. It revealed that the combined estimated prevalence of good knowledge about Coronavirus disease 2019, positive attitudes, and good practices among pregnant women was found to be 61.8 % (95 % CI: 53.0%-70.65 %; I2 = 98.7 %), 51.7 % (95 % CI: 30.34%-73.6 %; I2 = 99.3 %), and 52.31 % (95 % CI: 41.48%-63.15 %; I2 = 98.8 %) respectively.

Conclusion

This study emphasizes a significant concern: pregnant women exhibit a notable lack of knowledge, positive attitudes, and preventive practices regarding Coronavirus disease 2019. Considering their heightened vulnerability, urgent action is required to improve their understanding, attitudes, and behaviours related to the virus. Healthcare professionals should take proactive measures to educate pregnant women, addressing this crucial gap through various strategies.

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.

Temporal trends and spatial clusters of high risk for maternal death due to COVID-19 pre and during COVID-19 vaccination in Brazil: a national population-based ecological study

OBJECTIVE

This study comprehensively analyzed the temporal and spatial dynamics of COVID-19 cases and deaths within the obstetric population in Brazil, comparing the periods before and during mass COVID-19 vaccination. We explored the trends and geographical patterns of COVID-19 cases and maternal deaths over time. We also examined their correlation with the SARS-CoV-2 variant circulating and the social determinants of health.

STUDY DESIGN

This is a nationwide population-based ecological study.

METHODS

We obtained data on COVID-19 cases, deaths, socioeconomic status, and vulnerability information for Brazil's 5570 municipalities for both the pre-COVID-19 vaccination and COVID-19 vaccination periods. A Bayesian model was used to mitigate indicator fluctuations. The spatial correlation of maternal cases and fatalities with socioeconomic and vulnerability indicators was assessed using bivariate Moran.

RESULTS

From March 2020 to June 2023, a total of 23,823 cases and 1991 maternal fatalities were recorded among pregnant and postpartum women. The temporal trends in maternal incidence and mortality rates fluctuated over the study period, largely influenced by widespread COVID-19 vaccination and the dominant SARS-CoV-2 variant. There was a significant reduction in maternal mortality due to COVID-19 following the introduction of vaccination. The geographical distribution of COVID-19 cases and maternal deaths exhibited marked heterogeneity in both periods, with distinct spatial clusters predominantly observed in the North, Northeast, and Central West regions. Municipalities with the highest Human Development Index reported the highest incidence rates, while those with the highest levels of social vulnerability exhibited elevated mortality and fatality rates.

CONCLUSION

Despite the circulation of highly transmissible variants of concern, maternal mortality due to COVID-19 was significantly reduced following the mass vaccination. There was a heterogeneous distribution of cases and fatalities in both periods (before and during mass vaccination). Smaller municipalities and those grappling with social vulnerability issues experienced the highest rates of maternal mortality and fatalities.

Etiologically Based Functional Taxonomy of the Preterm Birth Syndrome

Preterm birth (PTB) is a complex syndrome traditionally defined by a single parameter, namely, gestational age at birth (ie, ˂37 weeks). This approach has limitations for clinical usefulness and may explain the lack of progress in identifying cause-specific effective interventions. The authors offer a framework for a functional taxonomy of PTB based on (1) conceptual principles established a priori; (2) known etiologic factors; (3) specific, prospectively identified obstetric and neonatal clinical phenotypes; and (4) postnatal follow-up of growth and development up to 2 years of age. This taxonomy includes maternal, placental, and fetal conditions routinely recorded in data collection systems.

Seroprevalence and placental transfer of SARS-CoV-2 antibodies in unvaccinated pregnant women

PURPOSE

Pregnant women are at risk of severe SARS-CoV-2 infection, potentially leading to obstetric and neonatal complications. Placental transfer of antibodies directed to SARS-CoV-2 may be protective against neonatal COVID-19, but this remains to be studied. We aimed to determine the seroprevalence of SARS-CoV-2 antibodies in a population of unvaccinated pregnant women and to determine the placental transfer of these antibodies.

METHODOLOGY

A total of 1197 unvaccinated women with mostly unknown pre-study SARS-CoV-2 infection status, were tested at delivery for SARS-CoV-2 spike protein IgG antibodies during the first year of the pandemic. Umbilical cord samples were collected and assessed for seropositivity if the mother was seropositive. Maternal characteristics, pregnancy and neonatal outcomes and data on SARS-CoV-2 infection were extracted from medical records.

RESULTS

Specific IgG were detected in 258 women (21.6%). A significant placental transfer to the newborn was observed in 81.3% of cases. The earlier in the 2nd and 3rd trimesters that the mother had contracted the disease and the more symptomatic she was, the greater the likelihood of transplacental transfer of IgG to her newborn.

CONCLUSION

Approximately one in five women had detectable anti-SARS-CoV-2 spike protein IgG antibodies at delivery during the first year of the pandemic, and these antibodies were significantly transferred to their fetuses. This research provides further evidence to better understand the dynamics of the placental transfer of SARS-CoV-2 IgG antibodies from mothers to their newborns, which is necessary to improve vaccination strategies.

COVID-19 Vaccination Strategies in the Endemic Period: Lessons from Influenza

Coronavirus disease 2019 (COVID-19) is a highly contagious zoonotic respiratory disease with many similarities to influenza. Effective vaccines are available for both; however, rapid viral evolution and waning immunity make them virtually impossible to eradicate with vaccines. Thus, the practical goal of vaccination is to reduce the incidence of serious illnesses and death. Three years after the introduction of COVID-19 vaccines, the optimal vaccination strategy in the endemic period remains elusive, and health authorities worldwide have begun to adopt various approaches. Herein, we propose a COVID-19 vaccination strategy based on the data available until early 2024 and discuss aspects that require further clarification for better decision making. Drawing from comparisons between COVID-19 and influenza vaccination strategies, our proposed COVID-19 vaccination strategy prioritizes high-risk groups, emphasizes seasonal administration aligned with influenza vaccination campaigns, and advocates the co-administration with influenza vaccines to increase coverage.

COVID-19 vaccine safety during pregnancy and breastfeeding in women with autoimmune diseases: results from the COVAD study

OBJECTIVES

We investigated coronavirus disease 2019 (COVID-19) vaccine safety in pregnant and breastfeeding women with autoimmune diseases (AID) in the COVID-19 Vaccination in Autoimmune Diseases (COVAD) study.

METHODS

Delayed-onset (>7 days) vaccine-related adverse events (AE), disease flares and AID-related treatment modifications were analysed upon diagnosis of AID vs healthy controls (HC) and the pregnancy/breastfeeding status at the time of at least one dose of vaccine.

RESULTS

Among the 9201 participants to the self-administered online survey, 6787 (73.8%) were women. Forty pregnant and 52 breastfeeding patients with AID were identified, of whom the majority had received at least one dose of COVID-19 vaccine (100% and 96.2%, respectively). AE were reported significantly more frequently in pregnant than in non-pregnant patients (overall AE 45% vs 26%, P = 0.01; minor AE 40% vs 25.9%, P = 0.03; major AE 17.5% vs 4.6%, P < 0.01), but no difference was found in comparison with pregnant HC. No difference was observed between breastfeeding patients and HC with respect to AE. Post-vaccination disease flares were reported by 17.5% of pregnant and 20% of breastfeeding patients, and by 18.3% of age- and disease-matched non-pregnant and non-breastfeeding patients (n = 262). All pregnant/breastfeeding patients who experienced a disease flare were managed with glucocorticoids; 28.6% and 20% of them required initiation or change in immunosuppressants, respectively.

CONCLUSION

This study provides reassuring insights into the safety of COVID-19 vaccines administered to women with AID during the gestational and post-partum periods, helping overcome hesitant attitudes, as the benefits for the mother and for the fetus by passive immunization appear to outweigh potential risks.

Maternal COVID-19 vaccination status and association with neonatal congenital anomalies

Introduction

Despite recommendations for COVID-19 vaccination in pregnant people, the effect of vaccination on neonatal outcomes remains unknown. We sought to determine the association between COVID-19 vaccination status in pregnancy and presence of neonatally diagnosed congenital anomalies.

Methods

A comprehensive vaccine registry was combined with a delivery database to create a cohort including all patients aged 16-55 years with a delivery event between December 10, 2020 and December 31, 2021 at a hospital within the Mayo Clinic Health System. Pregnancy and neonatal outcomes were analyzed in relation to vaccination status and timing, including a composite measure of congenital anomalies diagnosed in neonatal life. Comparisons between cohorts were conducted using chi-square test for categorical and Kruskal-Wallis test for continuous variables. A multivariable logistic regression was modeled to assess the association with congenital anomalies.

Results

5,096 mother-infant pairs were analyzed. A total of 1,158 were vaccinated, with 314 vaccinated in the first trimester. COVID-19 vaccination status, including vaccination during the first trimester of pregnancy, was not associated with an increased risk of composite congenital anomalies. When further examining congenital anomalies by organ system, we did demonstrate a significant difference in eye, ear, face, neck anomalies between vaccinated and not vaccinated groups (Table 3, Not vaccinated = 2.3%, Vaccinated = 3.3%, p-value 0.04) however we did not demonstrate this difference between the 1st trimester and not vaccinated groups (Not vaccinated = 2.3%, 1st Trimester = 2.5%, p-value 0.77). No differences were found between not vaccinated, vaccinated, or 1st trimester vaccinated groups for any other organ systems. There were no differences in birthweight by gestational age, APGAR scores, incidence of NICU admission, or living status of the neonate by vaccination status.

Conclusion

We add additional information regarding the safety of COVID-19 vaccination status and timing as it pertains to neonatal composite congenital anomalies, with no association demonstrated. Our findings agree with prior literature that COVID-19 vaccination is not associated with adverse pregnancy outcomes or small for gestational age neonates. Further research is needed to elucidate the association between COVID-19 vaccination and eye, ear, face, neck, anomalies.

Facilitators and barriers to vaccination uptake in pregnancy: A qualitative systematic review

INTRODUCTION

Vaccination during pregnancy protects both the mother and the foetus from vaccine-preventable diseases. However, uptake of the recommended vaccines (influenza, pertussis, COVID-19) by pregnant women remains low in Europe and the USA. Understanding the reasons for this is crucial to inform strategies to increase vaccination rates in pregnant women. This qualitative systematic review aimed to identify the barriers and facilitators to vaccination against influenza, pertussis/whooping cough and COVID-19 during pregnancy and identify possible strategies to increase vaccination rates.

METHODS

We conducted a comprehensive search of electronic databases, including Medline, PsycINFO, CINAHL, Web of Science, WHO database, Embase and grey literature to identify qualitative studies that explored barriers and facilitators to vaccine uptake among pregnant women (PROSPERO CRD42023399488). The search was limited to studies published between 2012 and 2022 conducted in high-income countries with established vaccination programmes during pregnancy. Studies were thematically analysed and underwent quality assessment using the Joanna Briggs Institute validated critical appraisal tool for qualitative research.

RESULTS

Out of 2681 articles screened, 28 studies (n = 1573 participants) were eligible for inclusion. Five overarching themes emerged relating to personal, provider and systemic factors. Barriers to vaccine uptake included concerns about vaccine safety and efficacy, lack of knowledge about vaccines' benefits and necessity, fear of adverse effects on the foetus or mother and low perception of disease severity. Facilitators included recommendations from trusted healthcare providers, easy access to vaccination, clear communication on the benefits and safety of vaccination, and positive social influences from family and friends. Strategies for increasing vaccination uptake included strong and proactive vaccine recommendations by trusted healthcare professionals, provision of vaccines during routine antenatal care, and clear and consistent communication about vaccines addressing pregnant women's concerns.

CONCLUSION

This review highlights the need for interventions that address the identified barriers to vaccine uptake among pregnant women. Recommendation from a healthcare provider can play a significant role in promoting vaccine uptake, as can clear risk/benefit communication and convenient access to vaccination. Addressing concerns about vaccine safety and providing accurate information about vaccines is also important.

Effectiveness and safety of COVID-19 vaccines on maternal and perinatal outcomes: a systematic review and meta-analysis

OBJECTIVE

To assess the effects of COVID-19 vaccines in women before or during pregnancy on SARS-CoV-2 infection-related, pregnancy, offspring and reactogenicity outcomes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Major databases between December 2019 and January 2023.

STUDY SELECTION

Nine pairs of reviewers contributed to study selection. We included test-negative designs, comparative cohorts and randomised trials on effects of COVID-19 vaccines on infection-related and pregnancy outcomes. Non-comparative cohort studies reporting reactogenicity outcomes were also included.

QUALITY ASSESSMENT, DATA EXTRACTION AND ANALYSIS

Two reviewers independently assessed study quality and extracted data. We undertook random-effects meta-analysis and reported findings as HRs, risk ratios (RRs), ORs or rates with 95% CIs.

RESULTS

Sixty-seven studies (1 813 947 women) were included. Overall, in test-negative design studies, pregnant women fully vaccinated with any COVID-19 vaccine had 61% reduced odds of SARS-CoV-2 infection during pregnancy (OR 0.39, 95% CI 0.21 to 0.75; 4 studies, 23 927 women; I2=87.2%) and 94% reduced odds of hospital admission (OR 0.06, 95% CI 0.01 to 0.71; 2 studies, 868 women; I2=92%). In adjusted cohort studies, the risk of hypertensive disorders in pregnancy was reduced by 12% (RR 0.88, 95% CI 0.82 to 0.92; 2 studies; 115 085 women), while caesarean section was reduced by 9% (OR 0.91, 95% CI 0.85 to 0.98; 6 studies; 30 192 women). We observed an 8% reduction in the risk of neonatal intensive care unit admission (RR 0.92, 95% CI 0.87 to 0.97; 2 studies; 54 569 women) in babies born to vaccinated versus not vaccinated women. In general, vaccination during pregnancy was not associated with increased risk of adverse pregnancy or perinatal outcomes. Pain at the injection site was the most common side effect reported (77%, 95% CI 52% to 94%; 11 studies; 27 195 women).

CONCLUSION

COVID-19 vaccines are effective in preventing SARS-CoV-2 infection and related complications in pregnant women.

PROSPERO REGISTRATION NUMBER

CRD42020178076.

Maternal hybrid immunity and risk of infant COVID-19 hospitalizations: national case-control study in Israel

Hybrid immunity, acquired through vaccination followed or preceded by a COVID-19 infection, elicits robust antibody augmentation. We hypothesize that maternal hybrid immunity will provide greater infant protection than other forms of COVID-19 immunity in the first 6 months of life. We conducted a case-control study in Israel, enrolling 661 infants up to 6 months of age, hospitalized with COVID-19 (cases) and 59,460 age-matched non-hospitalized infants (controls) between August 24, 2021, and March 15, 2022. Infants were grouped by maternal immunity status at delivery: Naïve (never vaccinated or tested positive, reference group), Hybrid-immunity (vaccinated and tested positive), Natural-immunity (tested positive before or during the study period), Full-vaccination (two-shot regimen plus 1 booster), and Partial-vaccination (less than full three shot regimen). Applying Cox proportional hazards models to estimate the hazard ratios, which was then converted to percent vaccine effectiveness, and using the Naïve group as the reference, maternal hybrid-immunity provided the highest protection (84% [95% CI 75-90]), followed by full-vaccination (66% [95% CI 56-74]), natural-immunity (56% [95% CI 39-68]), and partial-vaccination (29% [95% CI 15-41]). Maternal hybrid-immunity was associated with a reduced risk of infant hospitalization for Covid-19, as compared to natural-immunity, regardless of exposure timing or sequence. These findings emphasize the benefits of vaccinating previously infected individuals during pregnancy to reduce COVID-19 hospitalizations in early infancy.

Impact of the COVID-19 pandemic on excess maternal deaths in Brazil: A two-year assessment

BACKGROUND

Accurate estimates of the COVID-19 pandemic's indirect impacts are crucial, especially in low- and middle-income countries. This study aims to update estimates of excess maternal deaths in Brazil during the first two years of the COVID-19 pandemic.

METHODS

This was an exploratory mixed ecological study using the counterfactual approach. The observed maternal deaths were gathered from the Mortality Information System (SIM) for the period between March 2015 and February 2022. Expected deaths from March 2020 to February 2022 were estimated using quasipoisson generalized additive models, considering quadrimester, age group, and their interaction as predictor variables. Analyses were performed in R version 4.1.2, RStudio, version 2023.03.1+446 and carried out with support from the "mgcv" and "plot_model" libraries.

RESULTS

A total of 5,040 maternal deaths were reported, with varying excess mortality across regions and age groups, resulting in 69% excess maternal mortality throughout Brazil during the first two years of the pandemic. The Southeast region had 50% excess mortality throughout the first two years and 76% excess in the second year. The North region had 69% excess mortality, increasing in the second year, particularly among women aged 20-34. The Northeast region showed 80% excess mortality, with a significant increase in the second year, especially among women aged 35-49. The Central-West region had 75% excess mortality, higher in the second year and statistically significant among women aged 35-49. The South region showed 117% excess mortality, reaching 203% in the second year among women aged 20-34, but no excess mortality in the 10-19 age category.

CONCLUSIONS

Over two years, Brazil saw a significant impact on maternal excess deaths, regardless of region and pandemic year. The highest peak occurred between March and June 2021, emphasizing the importance of timely and effective epidemic responses to prevent avoidable deaths and prepare for new crises.

Awareness and Safety of COVID-19 Vaccination in Pregnancy

Background

COVID-19 vaccines are safe in pregnancy, as they do not contain a live attenuated virus. Mass vaccination is a key to control the pandemic. Neonates have been shown to be susceptible to severe illness, so maternal vaccination is important to provide neonatal vaccination.

Methods

The present study was conducted for a period of one year from November 21, 2021 to October 2O, 2022 at the Department of Obstetrics and Gynecology A.S.J.S.A.T.D.S. medical college, Fatehpur. It was a hospital-based cross-sectional study. This study aimed to investigate the efficacy, safety, attitude, side effect and maternal neonatal outcome of COVID-19 vaccination among pregnant women.

Results

Out of 3320 pregnant women delivered, only 1170 (35.24%) received at least one dose of COVID-19 vaccine. 69.23% were unaware of the type of COVID-19 vaccine. 66.15% were vaccinated for both the doses before pregnancy. 12.30% of women had taken only the first dose of COVID vaccine before pregnancy. Majority had fever with chills after the first dose. Fatigue was most common side effect after second dose, and no one had any rash or allergic reaction. 56.15% delivered vaginally, 37.69% had LSCS for different obstetric indications, and 6.15% had instrumental delivery. During the antenatal period, 38.46% developed anemia, 11.54% had preterm labor, 2.05% had gestational diabetes, 2.30% developed preeclampsia, and 3.85% developed hypothyroidism. 3.07% prolonged labor in intrapartum period, and 6.92% women developed PPH. 50.77% newborns were between 2.5 and 2.9 kg, and majority 71.54% newborns had an APGAR score of 7 or more at 5 minutes. 14.62% newborns had meconium aspiration syndrome, 3.84% had respiratory distress syndrome, and 20.34% needed NICU admission more than 24 hours.

Conclusion

Available data do not support increased risk of adverse outcome following COVID-19 vaccination. We recommend vaccination during pregnancy as benefit outweigh the potential risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13224-023-01918-w.

Prevalence of COVID-19 among pregnant women and its impact on childbirth in March 2021: Data from the French National Perinatal Survey

BACKGROUND

Several series reported obstetric complications among pregnant women hospitalized for COVID. These data, because they focused on women with the most severe presentations or with specific immunosuppression, were likely to overestimate the risks associated with the infection at a global level. To date, population-based studies, most of which collected data from registers of women hospitalized during pregnancy for COVID-19, remain sparse. Neither the prevalence of COVID-19 in pregnant women nor the overall extent of obstetric complications worldwide, compared with uninfected pregnant women is clear. The impact of COVID-19 on perinatal care and obstetric management is thus difficult to evaluate.

OBJECTIVES

To evaluate the prevalence and determinants of COVID-19 diagnosis during pregnancy and assess related obstetric practices and perinatal outcomes.

STUDY DESIGN

Used data collected at childbirth in France from women included in the 2021 national perinatal survey, we compared women with and without a COVID-19 diagnosis (for sociodemographic characteristics) and then women with no COVID-19 diagnosis during pregnancy, women diagnosed more than 15 days preceding childbirth, and those diagnosed within those 15 days for outcomes.

RESULTS

The COVID-19 prevalence during pregnancy was 5.7 % (95 %CI 5.3-6.1) (678/11 930). The aOR for COVID-19 diagnosis associated with non-French nationality was 1.27 (95 %CI 1.03-1.58), with non-smoking 0.63 (95 %CI 0.55-0.81) and with multiparity 1.21 (95 %CI 1.02-1.45). Diagnosis occurred in the third trimester for 49 % -28.5 % in the 15 days before childbirth. Women with COVID-19 diagnosed during pregnancy had preterm births more often (9.6 %) than women without this diagnosis (6.9 %) (P = 0.007). Women with COVID-19 diagnosed within the 15 days preceding childbirth had more cesarean deliveries (28.3 %) than those diagnosed earlier (17.4 %) (P = 0.02).

CONCLUSIONS

COVID-19 diagnosis during pregnancy was associated with an increased risk of preterm birth. Obstetric outcomes were poorer in women with a COVID-19 diagnosis in the 15 days preceding childbirth.

The COVID-19 International Drug Pregnancy Registry (COVID-PR): Protocol Considerations

BACKGROUND AND OBJECTIVE

Over the past 2 years, several drugs have been approved for coronavirus disease 2019 (COVID-19) treatment, but their safety during pregnancy remains poorly understood. This study aims to assess the relative risk of obstetric, neonatal, and infant outcomes associated with the use of drugs specifically indicated for the treatment of COVID-19 compared with other drug treatment strategies. The purpose of this article is to present elements of the study protocol.

METHODS

The COVID-19 International Drug Pregnancy Registry (COVID-PR) is a noninterventional, postmarketing cohort study. Pregnant women receiving treatment with monoclonal antibodies (mAbs) or antiviral drugs for mild, moderate, or severe COVID-19 are matched 1:1 with pregnant women not receiving these study-specific drugs, based on calendar time, country, gestational age at enrollment, and COVID-19 severity. Participants complete online questionnaires at enrollment, during pregnancy, and for 12 months after delivery of liveborn infants. The study began enrolling participants on 1 December 2021 and is set to span 5 years for each drug of interest.

DISCUSSION

The COVID-PR is designed to evaluate the safety profile of each studied drug. Additionally, it may allow for an analysis of the effects of COVID-19 drug exposure during relevant gestational periods on specific neonatal outcomes. Although the sample size will be too small to detect associations with rare outcomes, the study has the potential to generate hypotheses for future research. Ultimately, these data can provide valuable insights for evidence-based decisions about COVID-19 treatment during pregnancy.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT05013632. EU PAS EUPAS42517.

SARS-CoV-2 perinatal transmission and neonatal outcomes across four different waves of COVID-19 pandemic: A nationwide prospective cohort study from the Italian Society of Neonatology

OBJECTIVES

To describe how SARS-CoV-2 infection at the time of delivery affected maternal and neonatal outcomes across four major waves of the COVID-19 pandemic in Italy.

METHODS

This is a large, prospective, nationwide cohort study collecting maternal and neonatal data in case of maternal peripartum SARS-CoV-2 infection between February 2020 and March 2022. Data were stratified across the four observed pandemic waves.

RESULTS

Among 5201 COVID-19-positive mothers, the risk of being symptomatic at delivery was significantly higher in the first and third waves (20.8-20.8%) than in the second and fourth (13.2-12.2%). Among their 5284 neonates, the risk of prematurity (gestational age <37 weeks) was significantly higher in the first and third waves (15.6-12.5%). The risk of intrauterine transmission was always very low, while the risk of postnatal transmission during rooming-in was higher and peaked at 4.5% during the fourth wave. A total of 80% of positive neonates were asymptomatic.

CONCLUSION

The risk of adverse maternal and neonatal outcomes was significantly higher during the first and third waves, dominated by unsequenced variants and the Delta variant, respectively. Postnatal transmission accounted for most neonatal infections and was more frequent during the Omicron period. However, the paucity of symptoms in infected neonates should lead us not to separate the dyad.

Planning for the future of maternal immunization: Building on lessons learned from the COVID-19 pandemic

As the worldwide COVID-19 pandemic unfolded, the clinical and public health community raced to understand SARS-CoV-2 infection and develop life-saving vaccines. Pregnant persons were disproportionately impacted, experiencing more severe illness and adverse pregnancy outcomes. And yet, when COVID-19 vaccines became available in late 2020, safety and efficacy data were not available to inform their use during pregnancy because pregnant persons were excluded from pre-authorization clinical trials. Concerns about vaccine safety during pregnancy and misinformation linking vaccination and infertility circulated widely, creating a lack of vaccine confidence. Many pregnant people initially chose not to get vaccinated, and while vaccination rates rose after safety and effectiveness data became available, COVID-19 vaccine acceptance was suboptimal and varied across racial and ethnic distribution of the pregnant population. The COVID-19 pandemic experience provided valuable insights that can inform current and future approaches to maternal vaccination against.

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.

Clinical course and management of COVID-19 in the era of widespread population immunity

The clinical implications of COVID-19 have changed since SARS-CoV-2 first emerged in humans. The current high levels of population immunity, due to prior infection and/or vaccination, have been associated with a vastly decreased overall risk of severe disease. Some people, particularly those with immunocompromising conditions, remain at risk for severe outcomes. Through the course of the pandemic, variants with somewhat different symptom profiles from the original SARS-CoV-2 virus have emerged. The management of COVID-19 has also changed since 2020, with the increasing availability of evidence-based treatments in two main classes: antivirals and immunomodulators. Selecting the appropriate treatment(s) for patients with COVID-19 requires a deep understanding of the evidence and an awareness of the limitations of applying data that have been largely based on immune-naive populations to patients today who most likely have vaccine-derived and/or infection-derived immunity. In this Review, we provide a summary of the clinical manifestations and approaches to caring for adult patients with COVID-19 in the era of vaccine availability and the dominance of the Omicron subvariants, with a focus on the management of COVID-19 in different patient groups, including immunocompromised, pregnant, vaccinated and unvaccinated patients.

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.

Multi-organ dysfunction and outcomes in pregnancy associated COVID-19 infection - descriptive review of pathological findings

OBJECTIVE(S)

Comparative clinical and morphological characterization of lesions of the vascular and nervous system in cases of maternal death associated with COVID-19.

STUDY DESIGN

The study included autopsy in 12 cases of maternal death with a positive intravital result for SARS-CoV-2 by reverse transcription polymerase chain reaction. For histopathology, tissue samples were taken from the internal organs of each patient. Pieces of organs were fixed and stained according to the standard protocol. The relative number of microvessels with vasculitis and fibers of the peripheral nervous system with infiltration by immune cells was studied. All morphological changes were classified depending on the severity of the damage.

RESULTS

The average age of patients with a fatal outcome was 35 ± 4.4 years. Time to death after onset of symptoms averaged 16 ± 4.4 days. Dystrophic lesions (necrosis and apoptosis) of the villous and extravillous trophoblast and decidual tissue were observed in the studied placentas. Histopathological signs of mild and severe lesions of the peripheral nervous system in the organs of the gastrointestinal tract were detected in 2 (16.7%) and 10 (83.3%) cases, respectively, in the myocardium in 4 (33.3%) and 8 (66.7%) cases. Histopathological signs of severe damage to the microvascular bed in the organs of the gastrointestinal tract were registered in 9 (75%) cases.

CONCLUSION(S)

The main clinical feature of this cohort was that death occurred in a long-term period, in most cases with a negative PCR. The histopathological pattern was a non-acute injury with an immune component of the microvascular bed and the autonomic nervous system with predominant damage to the myocardium and intestines.

WHAT DOES THIS STUDY ADD TO THE CLINICAL WORK

This study makes it possible to even better study the immunopathological profile in organs and tissues in pregnant women with a fatal outcome when affected by a viral infection, in particular Covid-19. This knowledge can be used when humanity encounters other viral pandemics in the future.

Timing of Maternal COVID-19 Vaccine and Antibody Concentrations in Infants Born Preterm

Importance

COVID-19 vaccine-derived antibodies in pregnant people may protect infants from severe infection in the first 6 months of life via transplacental antibody transfer. Few data exist on maternally derived SARS-CoV-2 antibodies in preterm compared with full-term infants in association with vaccination timing.

Objective

To compare SARS-CoV-2 anti-Spike (anti-S) antibody levels in preterm and full-term infants in the context of vaccine dose timing before delivery.

Design, Setting, and Participants

This prospective cohort study enrolled pregnant individuals and collected paired maternal and cord blood samples at delivery at the University of Washington between February 1, 2021, and January 31, 2023. Participants who had received at least 2 doses of a messenger RNA COVID-19 vaccine before delivery and did not have a history of prior COVID-19 infection or detectable anti-SARS-CoV-2 nucleocapsid antibodies were included.

Exposures

Timing of the last vaccine dose and preterm or full-term gestational age at delivery.

Main Outcomes and Measures

Paired maternal and cord samples were tested for anti-S antibody, and linear regression was used to evaluate associations between preterm delivery and anti-S antibody levels. Covariates included timing of last dose, number of doses, insurance status, and immunosuppressing medications.

Results

A total of 220 participants (median [IQR] age, 34 [32-37] years; 212 [96.4%] female) with 36 preterm and 184 full-term deliveries were studied. Before delivery, 121 persons received 2 vaccine doses and 99 persons received 3 or more vaccine doses. The geometric mean concentration of maternal anti-S antibodies was 674 (95% CI, 577-787) after 2 doses and 8159 (95% CI, 6636-10 032) after 3 or more doses (P < .001). The cord anti-S antibody geometric mean concentration was 1000 (95% CI, 874-1144) after 2 doses and 9992 (95% CI, 8381-11 914) after 3 or more doses (P < .001). After adjustment for vaccine timing and number of doses before delivery, no association was found between preterm delivery and cord anti-S antibody levels (β = 0.44; 95% CI, -0.06 to 0.94).

Conclusions and Relevance

In this prospective cohort study of pregnant individuals with preterm and full-term deliveries, receipt of 3 or more compared with 2 doses of COVID-19 vaccine before delivery resulted in 10-fold higher cord anti-S antibody levels. Maternal antibody concentration appeared more important than delivery gestational age in determining cord anti-S antibody levels. The number of doses and timing considerations for COVID-19 vaccine in pregnancy should include individuals at risk for preterm delivery.

Nirmatrelvir/ritonavir use in pregnant women with SARS-CoV-2 Omicron infection: a target trial emulation

To date, there is a lack of randomized trial data examining the use of the antiviral nirmatrelvir/ritonavir in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected pregnant persons. This target trial emulation study aimed to address this gap by evaluating the use of nirmatrelvir/ritonavir in nonhospitalized pregnant women with symptomatic SARS-CoV-2 Omicron variant infection. Among patients diagnosed between 16 March 2022 and 5 February 2023, exposure was defined as outpatient nirmatrelvir/ritonavir treatment within 5 days of symptom onset or coronavirus disease 2019 (COVID-19) diagnosis. Primary outcomes were maternal morbidity and mortality index (MMMI), all-cause maternal death and COVID-19-related hospitalization, while secondary outcomes were individual components of MMMI, preterm birth, stillbirth, neonatal death and cesarean section. One-to-ten propensity-score matching was conducted between nirmatrelvir/ritonavir users and nonusers, followed by cloning, censoring and weighting. Overall, 211 pregnant women on nirmatrelvir/ritonavir and 1,998 nonusers were included. Nirmatrelvir/ritonavir treatment was associated with reduced 28-day MMMI risk (absolute risk reduction (ARR) = 1.47%, 95% confidence interval (CI) = 0.21-2.34%) but not 28-days COVID-19-related hospitalization (ARR = -0.09%, 95% CI = -1.08% to 0.71%). Nirmatrelvir/ritonavir treatment was also associated with reduced risks of cesarean section (ARR = 1.58%, 95% CI = 0.85-2.39%) and preterm birth (ARR = 2.70%, 95% CI = 0.98-5.31%). No events of maternal or neonatal death or stillbirth were recorded. The findings suggest that nirmatrelvir/ritonavir is an effective treatment in symptomatic pregnant women with SARS-CoV-2 Omicron variant infection.

Pre-Delta, Delta, and Omicron Periods of the Coronavirus Disease 2019 (COVID-19) Pandemic and Health Outcomes During Delivery Hospitalization

OBJECTIVE

To examine the relationship between coronavirus disease 2019 (COVID-19) diagnosis at delivery and adverse maternal health and pregnancy outcomes during pre-Delta, Delta, and Omicron variant predominance, with a focus on the time period of Omicron variant predominance.

METHODS

We conducted a cross-sectional observational study with data from delivery hospitalizations in the Premier Healthcare Database from February 2020 to August 2023. The pre-Delta (February 2020-June 2021), Delta (July 2021-December 2021), and Omicron (January 2022-August 2023) periods of variant predominance were examined. Exposure to COVID-19 was identified by having a diagnostic code for COVID-19 during the delivery hospitalization. Adjusted prevalence ratios (aPRs) were calculated to compare the risks of adverse maternal and pregnancy outcomes for women with and without COVID-19 diagnoses at the time of delivery for each variant period.

RESULTS

Among 2,990,973 women with delivery hospitalizations, 1.9% (n=56,618) had COVID-19 diagnoses noted at delivery admission discharge, including 26,053 during the Omicron period. Across all variant time periods, the prevalence of many adverse maternal and pregnancy outcomes during the delivery hospitalization was significantly higher for pregnant women with COVID-19 compared with pregnant women without COVID-19. In adjusted models, COVID-19 during the Omicron period was associated with significant increased risks for maternal sepsis (COVID-19: 0.4% vs no COVID-19: 0.1%; aPR 3.32, 95% CI, 2.70-4.08), acute respiratory distress syndrome (0.6% vs 0.1%; aPR 6.19, 95% CI, 5.26-7.29), shock (0.2% vs 0.1%; aPR 2.14, 95% CI, 1.62-2.84), renal failure (0.5% vs 0.2%; aPR 2.08, 95% CI, 1.73-2.49), intensive care unit admission (2.7% vs 1.7%; aPR 1.64, 95% CI, 1.52-1.77), mechanical ventilation (0.3% vs 0.1%; aPR 3.15, 95% CI, 2.52-3.93), in-hospital death (0.03% vs 0.01%; aPR 5.00, 95% CI, 2.30-10.90), stillbirth (0.7% vs 0.6%; aPR 1.17, 95% CI, 1.01-1.36), and preterm delivery (12.3% vs 9.6%; aPR 1.28, 95% CI, 1.24-1.33).

CONCLUSION

Despite the possibility of some level of immunity due to previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, vaccination, or testing differences, risks of adverse outcomes associated with COVID-19 diagnosis at delivery remained elevated during the Omicron variant time period.

Safety of BNT162b2 and CoronaVac during pregnancy on birth outcomes and neonatal mortality: a cohort study from Brazil

BACKGROUND

COVID-19 vaccines have been shown to protect pregnant individuals against mild and severe COVID-19 outcomes. However, limited safety data are available for inactivated (CoronaVac) and mRNA (BNT162b2) vaccines during pregnancy regarding their effect on birth outcomes and neonatal mortality, especially in low- and middle-income countries.

METHODS

We conducted a retrospective population-based cohort study in Rio de Janeiro, Brazil, with 17 513 singleton live births conceived between 15 May 2021 and 23 October 2021. The primary exposure was maternal vaccination with CoronaVac or mRNA BNT162b2 vaccines and sub-analyses were performed by the gestational trimester of the first dose and the number of doses given during pregnancy. The outcomes were pre-term birth (PTB), small for gestational age (SGA), low birthweight (LBW), low Apgar 5 and neonatal death. We used the Cox model to estimate the hazard ratio (HR) with a 95% CI and applied the inverse probability of treatment weights to generate adjusted HRs.

RESULTS

We found no significant increase in the risk of PTB (HR: 0.98; 95% CI 0.88, 1.10), SGA (HR: 1.09; 95% CI 0.96, 1.27), LBW (HR: 1.00; 95% CI 0.88, 1.14), low Apgar 5 (HR: 0.81; 95% CI 0.55, 1.22) or neonatal death (HR: 0.88; 95% CI 0.56, 1.48) in women vaccinated with CoronaVac or BNT162b2 vaccines. These findings were consistent across sub-analyses stratified by the gestational trimester of the first dose and the number of doses given during pregnancy. We found mild yet consistent protection against PTB in women who received different vaccine platforms during the third trimester of pregnancy (any vaccines, HR: 0.78; 95% CI 0.63, 0.98; BNT162b2, HR: 0.75; 95% CI 0.59, 0.99).

CONCLUSIONS

This study provides evidence that COVID-19 vaccination in all trimesters of pregnancy, irrespective of the vaccine type, is safe and does not increase the risk of adverse birth outcomes or neonatal deaths.

Vaccination, immunity, and the changing impact of COVID-19 on infant health

In utero exposure to COVID-19 infection may lead to large intergenerational health effects. The impact of infection exposure has likely evolved since the onset of the pandemic as new variants emerge, immunity from prior infection increases, vaccines become available, and vaccine hesitancy persists, such that when infection is experienced is as important as whether it is experienced. We examine the changing impact of COVID-19 infection on preterm birth and the moderating role of vaccination. We offer the first plausibly causal estimate of the impact of maternal COVID-19 infection by using population data with no selectivity, universal information on maternal COVID-19 infection, and linked sibling data. We then assess change in this impact from 2020 to 2023 and evaluate the protective role of COVID-19 vaccination on infant health. We find a substantial adverse effect of prenatal COVID-19 infection on the probability of preterm birth. The impact was large during the first 2 y of the pandemic but had fully disappeared by 2022. The harmful impact of COVID-19 infection disappeared almost a year earlier in zip codes with high vaccination rates, suggesting that vaccines might have prevented thousands of preterm births. The findings highlight the need to monitor the changing consequences of emerging infectious diseases over time and the importance of mitigation strategies to reduce the burden of infection on vulnerable populations.