SARS-CoV-2 variants and pregnant Women: A cause for Concern?

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

A retrospective observational study on maternal and neonatal outcomes of COVID-19: Does the mild SARS-CoV-2 infection affect the outcome?

Background

Currently, several SARS-CoV-2 variants, including Omicron, are still circulating globally. This underscores the necessity for a comprehensive understanding of their impact on obstetric and neonatal outcomes in pregnant women, even in cases of mild infection.

Methods

We conducted a retrospective, single-center observational study to investigate the association between gestational SARS-CoV-2 infection and maternal-fetal outcomes in the Chinese population. The study enrolled 311 pregnant patients with SARS-CoV-2 infection (exposure group) and 205 uninfected pregnant patients (control group). We scrutinized the hospital records to collect data on demographics, clinical characteristics, and maternal and neonatal outcomes for subsequently comparison.

Results

Similar characteristics were observed in both groups, including maternal age, height, BMI, gravidity, parity, and comorbidities (p > 0.05). A majority (97.4%) of pregnant women in the exposure group with COVID-19 experienced mild clinical symptoms, with fever (86.5%) and cough (74.3%) as the primary symptoms. The exposure group exhibited significantly higher incidences of cesarean section and fetal distress compared to the control group (p < 0.05). Furthermore, pregnant women in the exposure group showed reduced levels of hemoglobin and high-sensitivity C-reactive protein, while experiencing significantly increased levels of lymphocytes, prothrombin time, alanine aminotransferase, and aspartate aminotransferase (p < 0.05). Notably, recent SARS-CoV-2 infection prior to delivery appeared to have an adverse impact on liver function, blood and coagulation levels in pregnant women. When comparing the two groups, there were no significant differences in the postpartum hemorrhage rate, premature birth rate, birth weight, neonatal asphyxia rate, neonatal department transfer rate, and neonatal pneumonia incidence.

Conclusions

Our study suggests that mild COVID-19 infection during pregnancy does not have detrimental effects on maternal and neonatal outcomes. However, the increased risks of events such as fetal distress and cesarean section, coupled with potential alterations in physical function, reveal the consequences of SARS-CoV-2 infection during pregnancy, even in mild cases. These findings emphasize the importance of proactive management and monitoring of pregnant individuals with COVID-19.

Infection with SARS-CoV-2 during pregnancy and risk of stillbirth: a Scandinavian registry study

Background

A few studies indicate that women infected with SARS-CoV-2 during pregnancy might have an increased risk of stillbirth. Our aim was to investigate the risk of stillbirth according to infection with SARS-CoV-2 during pregnancy also taking the variant into account.

Methods

We conducted a register-based study using the Swedish, Danish and Norwegian birth registries. A total of 389 949 births (1013 stillbirths) after 22 completed gestational weeks between 1 May 2020 and end of follow-up (27 January 2022 for Sweden and Norway; 31 December 2021 for Denmark). We estimated the risk of stillbirth following SARS-CoV-2 infection after 22 completed gestational weeks using Cox regression for each country, and combined the results using a random-effects meta-analysis.

Results

SARS-CoV-2 infection after 22 completed gestational weeks was associated with an increased risk of stillbirth (adjusted HR 2.40; 95% CI 1.22 to 4.71). The risk was highest during the first weeks following infection, with an adjusted HR of 5.48 (95% CI 3.11 to 9.63) during the first 2 weeks, 4.38 (95% CI 2.41 to 7.98) during the first 4 weeks, and 3.71 (95% CI 1.81 to 7.59) during the first 6 weeks. Furthermore, the risk was greatest among women infected during the Delta-dominated period (adjusted HR 8.23; 95% CI 3.65 to 18.59), and more modest among women infected during the Index (adjusted HR 3.66; 95% CI 1.89 to 7.06) and Alpha (adjusted HR 2.73; 95% CI 1.13 to 6.59) dominated periods.

Conclusions

We found an increased risk of stillbirth among women who were infected with SARS-CoV-2 after 22 gestational weeks, with the greatest risk during the Delta-dominated period.

Maternal and Perinatal Outcomes of SARS-CoV-2 and Variants in Pregnancy

Pregnancy is a physiological state that predisposes women to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, a disease that can cause adverse maternal and perinatal outcomes. The severity of coronavirus disease 2019 (COVID-19) disease is known to vary by viral strain; however, evidence for the effects of this virus in pregnant women has yet to be fully elucidated. In this review, we describe maternal and perinatal outcomes, vaccination, and vertical transmission, among pregnant women infected with the different SARS-CoV-2 variants identified to date. We also summarize existing evidence for maternal and perinatal outcomes in pregnant women with specific information relating to SARS-CoV-2 variants. Our analysis showed that Omicron infection was associated with fewer severe maternal and perinatal adverse outcomes while the Delta variant was associated with worse pregnancy outcomes. Maternal deaths arising from COVID-19 were found to be rare (<1.0%), irrespective of whether the virus was a wild-type strain or a variant. Severe maternal morbidity was more frequent for the Delta variant (10.3%), followed by the Alpha (4.7%), wild-type (4.5%), and Omicron (2.9%) variants. The rates of stillbirth were 0.8%, 4.1%, 3.1%, and 2.3%, respectively, in pregnancies infected with the wild-type strain, Alpha, Delta, and Omicron variants, respectively. Preterm birth and admission to neonatal intensive care units were more common for cases with the Delta infection (19.0% and 18.62%, respectively), while risks were similar for those infected with the wild-type (14.7% and 11.2%, respectively), Alpha (14.9% and 13.1%), and Omicron variants (13.2% and 13.8%, respectively). As COVID-19 remains a global pandemic, and new SARS-CoV-2 variants continue to emerge, research relating to the specific impact of new variants on pregnant women needs to be expanded.

Association of Infection with Different SARS-CoV-2 Variants during Pregnancy with Maternal and Perinatal Outcomes: A Systematic Review and Meta-Analysis

The aim of this study is to review the currently available data, and to explore the association of infection with different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants during pregnancy with maternal and perinatal outcomes in the real world. Observational cohort studies were analyzed that described the maternal and perinatal outcomes of infection with different SARS-CoV-2 variants during pregnancy. Random-effects inverse-variance models were used to evaluate the pooled prevalence (PP) and its 95% confidence interval (CI) for maternal and perinatal outcomes. Random effects were used to estimate the pooled odds ratios (OR) and their 95% CI for different outcomes between Delta and pre-Delta periods, and between Omicron and Delta periods. Eighteen studies, involving a total of 133,058 cases of SARS-CoV-2 infection during pregnancy (99,567 cases of SARS-CoV-2 wild type or pre-variant infection and 33,494 cases of SARS-CoV-2 variant infections), were included in this meta-analysis. Among pregnant women with SARS-CoV-2 infections, the PPs for required respiratory support, severe or critical illness, intensive care unit (ICU) admission, maternal death, and preterm birth <37 weeks were, respectively, 27.24% (95%CI, 20.51−33.97%), 24.96% (95%CI, 15.96−33.96%), 11.31% (95%CI, 4.00−18.61%), 4.20% (95%CI, 1.43−6.97%), and 33.85% (95%CI, 21.54−46.17%) in the Delta period, which were higher than those in the pre-Delta period, while the corresponding PPs were, respectively, 10.74% (95%CI, 6.05−15.46%), 11.99% (95%CI, 6.23−17.74%), 4.17% (95%CI, 1.53−6.80%), 0.63% (95%CI, 0.05−1.20%), and 18.58% (95%CI, 9.52−27.65%). The PPs for required respiratory support, severe or critical illness, and ICU admission were, respectively, 2.63% (95%CI, 0.98−4.28%), 1.11% (95%CI, 0.29−1.94%), and 1.83% (95%CI, 0.85−2.81%) in the Omicron period, which were lower than those in the pre-Delta and Delta periods. These results suggest that Omicron infections are associated with less severe maternal and neonatal adverse outcomes, though maternal ICU admission, the need for respiratory support, and preterm birth did also occur with Omicron infections. Since Omicron is currently the predominant strain globally, and has the highest rates of transmission, it is still important to remain vigilant in protecting the vulnerable populations of mothers and infants. In particular, obstetricians and gynecologists should not ignore the adverse risks of maternal ICU admission, respiratory support, and preterm births in pregnant patients with SARS-CoV-2 infections, in order to protect the health of mothers and infants.