Sars-CoV-2 in pregnancy: Why is it better than expected?

Mendelian randomization supports genetic liability to hospitalization for COVID-19 as a risk factor of pre-eclampsia

Background

Pre-eclampsia and eclampsia are among the major threats to pregnant women and fetuses, but they can be mitigated by prevention and early screening. Existing observational research presents conflicting evidence regarding the causal effects of coronavirus disease 2019 (COVID-19) on pre-eclampsia risk. Through Mendelian randomization (MR), this study aims to investigate the causal effect of three COVID-19 severity phenotypes on the risk of pre-eclampsia and eclampsia to provide more rigorous evidence.

Methods

Two-sample MR was utilized to examine causal effects. Summary-level data from genome-wide association studies (GWAS) of individuals of European ancestry were acquired from the GWAS catalog and FinnGen databases. Single-nucleotide polymorphisms associated with COVID-19 traits at p < 5 × -8 were obtained and pruned for linkage disequilibrium to generate instrumental variables for COVID-19. Inverse variance weighted estimates were used as the primary MR results, with weighted median and MR-Egger as auxiliary analyses. The robustness of the MR findings was also evaluated through sensitivity analyses. Bonferroni correction was applied to primary results, with a p < 0.0083 considered significant evidence and a p within 0.083-0.05 considered suggestive evidence.

Results

Critical ill COVID-19 [defined as hospitalization for COVID-19 with either a death outcome or respiratory support, OR (95% CI): 1.17 (1.03-1.33), p = 0.020] and hospitalized COVID-19 [defined as hospitalization for COVID-19, OR (95% CI): 1.10 (1.01-1.19), p = 0.026] demonstrated suggestive causal effects on pre-eclampsia, while general severe acute respiratory syndrome coronavirus 2 infection did not exhibit a significant causal effect on pre-eclampsia. None of the three COVID-19 severity phenotypes exhibited a significant causal effect on eclampsia.

Conclusions

Our investigation demonstrates a suggestive causal effect of genetic susceptibility to critical ill COVID-19 and hospitalized COVID-19 on pre-eclampsia. The COVID-19 severity exhibited a suggestive positive dose-response relationship with the risk of pre-eclampsia. Augmented attention should be paid to pregnant women hospitalized for COVID-19, especially those needing respiratory support.

Inhibition of IL-6 signaling prevents serum-induced umbilical cord artery dysfunction from patients with severe COVID-19

Coronavirus disease 2019 (COVID-19) infection has a negative impact on the cytokine profile of pregnant women. Increased levels of proinflammatory cytokines seem to be correlated with the severity of the disease, in addition to predisposing to miscarriage or premature birth. Proinflammatory cytokines increase the generation of reactive oxygen species (ROS). It is unclear how interleukin-6 (IL-6) found in the circulation of patients with severe COVID-19 might affect gestational health, particularly concerning umbilical cord function. This study tested the hypothesis that IL-6 present in the circulation of women with severe COVID-19 causes umbilical cord artery dysfunction by increasing ROS generation and activating redox-sensitive proteins. Umbilical cord arteries were incubated with serum from healthy women and women with severe COVID-19. Vascular function was assessed using concentration-effect curves to serotonin in the presence or absence of pharmacological agents, such as tocilizumab (antibody against the IL-6 receptor), tiron (ROS scavenger), ML171 (Nox1 inhibitor), and Y27632 (Rho kinase inhibitor). ROS generation was assessed by the dihydroethidine probe and Rho kinase activity by an enzymatic assay. Umbilical arteries exposed to serum from women with severe COVID-19 were hyperreactive to serotonin. This effect was abolished in the presence of tocilizumab, tiron, ML171, and Y27632. In addition, serum from women with severe COVID-19 increased Nox1-dependent ROS generation and Rho kinase activity. Increased Rho kinase activity was abolished by tocilizumab and tiron. Serum cytokines in women with severe COVID-19 promote umbilical artery dysfunction. IL-6 is key to Nox-linked vascular oxidative stress and activation of the Rho kinase pathway.

Outcome predictors and patient progress following delivery in pregnant and postpartum patients with severe COVID-19 pneumonitis in intensive care units in Israel (OB-COVICU): a nationwide cohort study

BACKGROUND

A key unresolved controversy in severe COVID-19 pneumonitis in pregnancy is the optimum timing of delivery and whether delivery improves or worsens maternal outcomes. We aimed to assess clinical data on every intensive care unit (ICU) day for pregnant and postpartum women admitted to the ICU with COVID-19, with a particular focus on the days preceding and following delivery.

METHODS

In this multicentre, nationwide, prospective and retrospective cohort study, we evaluated all pregnant women who were admitted to an ICU in Israel with severe COVID-19 pneumonitis from the 13th week of gestation to the 1st week postpartum. We excluded pregnant patients in which the ICU admission was unrelated to severe COVID-19 pneumonitis. We assessed maternal and neonatal outcomes and longitudinal clinical and laboratory ICU data. The primary overall outcome was maternal outcome (worst of the following: no invasive positive pressure ventilation [IPPV], use of IPPV, use of extracorporeal membrane oxygenation [ECMO], or death). The primary longitudinal outcome was Sequential Organ Failure Assessment (SOFA) score, and the secondary longitudinal outcome was the novel PORCH (positive end-expiratory pressure [PEEP], oxygenation, respiratory support, chest x-ray, haemodynamic support) score. Patients were classified into four groups: no-delivery (pregnant at admission and no delivery during the ICU stay), postpartum (ICU admission ≥1 day after delivery), delivery-critical (pregnant at admission and receiving or at high risk of requiring IPPV at the time of delivery), or delivery-non-critical (pregnant at admission and not critically ill at the time of delivery).

FINDINGS

From Feb 1, 2020, to Jan 31, 2022, 84 patients were analysed: 34 patients in the no-delivery group, four in postpartum, 32 in delivery-critical, and 14 in delivery-non-critical. The delivery-critical and postpartum groups had worse outcomes than the other groups: 26 (81%) of 32 patients in the delivery-critical group and four (100%) of four patients in the postpartum group required IPPV; 12 (38%) and three (75%) patients required ECMO, and one (3%) and two (50%) patients died, respectively. The delivery-non-critical and no-delivery groups had far better outcomes than other groups: six (18%) of 34 patients and two (14%) of 14 patients required IPPV, respectively; no patients required ECMO or died. Oxygen saturation (SpO₂), SpO₂ to fraction of inspired oxygen (FiO₂) ratio (S/F ratio), partial pressure of arterial oxygen to FiO₂ ratio (P/F ratio), ROX index (S/F ratio divided by respiratory rate), and SOFA and PORCH scores were all highly predictive for adverse maternal outcome (p<0·0001). The delivery-critical group deteriorated on the day of delivery, continued to deteriorate throughout the ICU stay, and took longer to recover (ICU duration, Mantel-Cox p<0·0001), whereas the delivery-non-critical group improved rapidly following delivery. The day of delivery was a significant covariate for PORCH (p<0·0001) but not SOFA (p=0·09) scores.

INTERPRETATION

In patients who underwent delivery during their ICU stay, maternal outcome deteriorated following delivery among those defined as critical compared with non-critical patients, who improved following delivery. Interventional delivery should be considered for maternal indications before patients deteriorate and require mechanical ventilation.

FUNDING

None.

Paradox of COVID-19 in pregnancy: are pregnant women more protected against or at elevated risk of severe COVID-19?

Many underlying medical conditions have been linked to worse COVID-19 prognosis. Based on reports on SARS-CoV-1 and Middle East respiratory syndrome infections, pregnancy has been considered a predisposing factor to severe COVID-19, with pregnant women being a high-risk group for several physiological reasons. Specifically, pregnant women undergo physiological adaptations that predispose them to severe respiratory viral diseases, including SARS-CoV-2. However, a significant amount of evidence suggests that the clinical outcome of COVID-19 among pregnant women is not different from the general population. In view of this, this report discusses the physiological conditions in pregnant women that adversely affect their immunity, cardiovascular homeostasis, and their endothelial and coagulopathic functions, thereby making them more prone to severe viral infections. We also discuss how these physiological adaptations appear to paradoxically offer protection against severe COVID-19 among pregnant women.

Pregnancy and the Risk of In-Hospital Coronavirus Disease 2019 (COVID-19) Mortality

OBJECTIVE

To evaluate whether pregnancy is an independent risk factor for in-hospital mortality among patients of reproductive age hospitalized with coronavirus disease 2019 (COVID-19) viral pneumonia.

METHODS

We conducted a retrospective cohort study (April 2020-May 2021) of 23,574 female inpatients aged 15-45 years with an International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis code for COVID-19 discharged from 749 U.S. hospitals in the Premier Healthcare Database. We used a viral pneumonia diagnosis to select for patients with symptomatic COVID-19. The associations between pregnancy and in-hospital mortality, intensive care unit (ICU) admission, and mechanical ventilation were analyzed using propensity score-matched conditional logistic regression. Models were matched for age, marital status, race and ethnicity, Elixhauser comorbidity score, payer, hospital number of beds, season of discharge, hospital region, obesity, hypertension, diabetes mellitus, chronic pulmonary disease, deficiency anemias, depression, hypothyroidism, and liver disease.

RESULTS

In-hospital mortality occurred in 1.1% of pregnant patients and 3.5% of nonpregnant patients hospitalized with COVID-19 and viral pneumonia (propensity score-matched odds ratio [OR] 0.39, 95% CI 0.25-0.63). The frequency of ICU admission for pregnant and nonpregnant patients was 22.0% and 17.7%, respectively (OR 1.34, 95% CI 1.15-1.55). Mechanical ventilation was used in 8.7% of both pregnant and nonpregnant patients (OR 1.05, 95% CI 0.86-1.29). Among patients who were admitted to an ICU, mortality was lower for pregnant compared with nonpregnant patients (OR 0.33, 95% CI 0.20-0.57), though mechanical ventilation rates were similar (35.7% vs 38.3%, OR 0.90, 95% CI 0.70-1.16). Among patients with mechanical ventilation, pregnant patients had a reduced risk of in-hospital mortality compared with nonpregnant patients (0.26, 95% CI 0.15-0.46).

CONCLUSION

Despite a higher frequency of ICU admission, in-hospital mortality was lower among pregnant patients compared with nonpregnant patients with COVID-19 viral pneumonia, and these findings persisted after propensity score matching.

Pregnant Women Develop a Specific Immunological Long-Lived Memory Against SARS-COV-2

It is well established that pregnancy induces deep changes in the immune system. This is part of the physiological adaptation of the female organism to the pregnancy and the immunological tolerance toward the fetus. Indeed, over the three trimesters, the suppressive T regulatory lymphocytes are progressively more represented, while the expression of co-stimulatory molecules decreases overtime. Such adaptations relate to an increased risk of infections and progression to severe disease in pregnant women, potentially resulting in an altered generation of long-lived specific immunological memory of infection contracted during pregnancy. How potent is the immune response against SARS-CoV-2 in infected pregnant women and how long the specific SARS-CoV-2 immunity might last need to be urgently addressed, especially considering the current vaccinal campaign. To address these questions, we analyzed the long-term immunological response upon SARS-CoV-2 infection in pregnant women from delivery to a six-months follow-up. In particular, we investigated the specific antibody production, T cell memory subsets, and inflammation profile. Results show that 80% developed an anti-SARS-CoV-2-specific IgG response, comparable with the general population. While IgG were present only in 50% of the asymptomatic subjects, the antibody production was elicited by infection in all the mild-to-critical patients. The specific T-cell memory subsets rebalanced over-time, and the pro-inflammatory profile triggered by specific SARS-CoV-2 stimulation faded away. These results shed light on SARS-CoV-2-specific immunity in pregnant women; understanding the immunological dynamics of the immune system in response to SARS-CoV-2 is essential for defining proper obstetric management of pregnant women and fine tune gender-specific vaccinal plans.

Pathophysiological and molecular considerations of viral and bacterial infections during maternal-fetal and -neonatal interactions of SARS-CoV-2, Zika, and Mycoplasma infectious diseases

During pregnancy, a series of physiological changes are determined at the molecular, cellular and macroscopic level that make the mother and fetus more susceptible to certain viral and bacterial infections, especially the infections in this and the companion review. Particular situations increase susceptibility to infection in neonates. The enhanced susceptibility to certain infections increases the risk of developing particular diseases that can progress to become morbidly severe. For example, during the current pandemic caused by the SARS-CoV-2 virus, epidemiological studies have established that pregnant women with COVID-19 disease are more likely to be hospitalized. However, the risk for intensive care unit admission and mechanical ventilation is not increased compared with nonpregnant women. Although much remains unknown with this particular infection, the elevated risk of progression during pregnancy towards more severe manifestations of COVID-19 disease is not associated with an increased risk of death. In addition, the epidemiological data available in neonates suggest that their risk of acquiring COVID-19 is low compared with infants (<12 months of age). However, they might be at higher risk for progression to severe COVID-19 disease compared with older children. The data on clinical presentation and disease severity among neonates are limited and based on case reports and small case series. It is well documented the importance of the Zika virus infection as the main cause of several congenital anomalies and birth defects such as microcephaly, and also adverse pregnancy outcomes. Mycoplasma infections also increase adverse pregnancy outcomes. This review will focus on the molecular, pathophysiological and biophysical characteristics of the mother/placental-fetal/neonatal interactions and the possible mechanisms of these pathogens (SARS-CoV-2, ZIKV, and Mycoplasmas) for promoting disease at this level.

Pregnancy as a Risk Factor of Severe COVID-19

Since first being identified in December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as an etiological agent behind Coronavirus disease 19 (COVID-19), has caused three waves of a global pandemic, with a fourth in progress. Despite its high percentage of asymptomatic and low-symptomatic courses of illness, the SARS-CoV-2 pandemic has claimed a higher death toll than the SARS-CoV and MERS-CoV epidemics because of its high infectivity when compared to the other coronaviruses. High COVID-19 mortality is associated with age and other coexisting morbidities, as well as healthcare quality. According to several studies, pregnant women are at a higher risk of severe COVID-19 infection and adverse pregnancy outcomes (caesarean delivery, pre-term birth, low birth weight, preeclampsia, ICU admission, and need for mechanical ventilation). In our review of recent literature, we focused on the effects of COVID-19 in pregnant women, emphasizing the subcellular pathophysiology of SARS-CoV-2. In this paper, we concentrate on the pathophysiology of sub-cellular changes in COVID-19 and endeavor to highlight the aspects that manifest in physiological pregnancy and potentially create a higher risk of SARS-CoV-2 infection and acute COVID-19 symptoms. Understanding how pregnancy-associated changes can cause a synergistic effect with COVID-19 may point us in the right direction for future prophylaxis and treatment for women undergoing COVID-19 during pregnancy.

Gasless laparoendoscopic single-site surgery for management of unruptured tubal pregnancy in a woman with moderate COVID-19 pneumonia after administration of remdesivir and casirivimab-imdevimab: A case report

Background

Diagnostic and therapeutic challenges may arise in the management of gynecologic emergencies, such as ectopic pregnancy, for women with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

Case

A 33-year-old woman (gravida 3, para 2) with a history of SARS-CoV-2 infection 8 months prior experienced sudden onset of fever and cough. Four days later, she consulted her gynecologist because of a positive pregnancy test and was further referred because of suspected ectopic pregnancy at 11 weeks of gestation, as calculated from her last irregular menstrual period. At triage, the patient complained of dyspnea, chest pain, and cough. Real-time reverse transcription-polymerase chain reaction assay detected SARS-CoV-2, which was subsequently identified to be an L452R variant. Chest computerized tomography (CT) showed moderate COVID-19 pneumonia. Transvaginal ultrasonography and pelvic CT showed a right tubal mass without an intrauterine gestational sac, suggesting right tubal pregnancy. Systemic methotrexate (MTX) therapy was chosen for management of the tubal pregnancy because of the patient's unruptured hemodynamically stable status, along with immediate administration of remdesivir and casirivimab-imdevimab to prevent worsening of the pneumonia. After failed MTX therapy, gasless laparoendoscopic single-site right salpingectomy was performed due to concern for tubal rupture. Four days after surgery, the patient was discharged from the hospital without subsequent complications.

Conclusions

Laparoscopic surgery, preceded by anti-viral therapy for COVID-19, is a feasible option for the management of hemodynamically stable tubal pregnancy in a woman with moderate COVID-19 pneumonia.

Screening of severe acute respiratory syndrome coronavirus-2 infection during labor and delivery using polymerase chain reaction and immunoglobulin testing

Aims

To assess severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection during labor and delivery with polymerase chain reaction (PCR) and using immunoglobulin G and M testing to correlate with maternal and perinatal outcomes.

Main methods

Pregnant women admitted for labor and delivery at two Spanish hospitals were screened for SARS-CoV-2 infection by PCR test and by detection of serum immunoglobulins G and M. Maternal and perinatal outcomes were compared in women with laboratory evidence of SARS-CoV-2 infection with those with negative tests.

Key findings

Between March 31st and September 30th, 2020, 1211 pregnant women were screened for SARS-CoV-2 infection. The prevalence of laboratory evidence of SARS-CoV-2 infections was 5.4% (n = 65), corresponding to (i) 22 ongoing infections at admission, including two with mild clinical symptoms and 20 asymptomatic women; (ii) 43 cases of previous SARS-CoV-2 exposure; (iii) and 1146 women who were negative for both SARS-CoV-2 PCR and serological test. None of the screened mothers required hospital admission for coronavirus disease before or after delivery, nor were any of the newborns admitted to the intensive care unit. All newborns from mothers with positive PCR on admission were PCR negative. There were no significant differences in maternal or perinatal outcomes among the three studied groups.

Significance

Ongoing or previous SARS-CoV-2 infection with asymptomatic or mild clinical symptoms detected during screening in pregnant women at labor and delivery do not have a higher rate of adverse maternal or perinatal outcomes.