Maternal and perinatal outcomes following pre-Delta, Delta, and Omicron SARS-CoV-2 variants infection among unvaccinated pregnant women in France and Switzerland: a prospective cohort study using the COVI-PREG registry.

BACKGROUND SARS-CoV-2 positive pregnant women are at higher risk of adverse outcomes, but little evidence is available on how variants impact that risk. We aim to evaluate maternal and perinatal outcomes among unvaccinated pregnant women that tested positive for SARS-CoV-2, stratified by pre-Delta, Delta, and Omicron periods. METHODS This prospective study enrolled women from March 2020 to September 2022. Exposure to the different SARS-CoV-2 variants was defined by their periods of predominance. The primary outcome was severe maternal adverse outcome defined as either intensive care unit admission, acute respiratory distress syndrome, advanced oxygen supplementation, or maternal death. The secondary outcomes were preterm birth and other perinatal outcomes. FINDINGS Overall, 1402, 262, and 391 SARS-CoV-2 positive pregnant women were enrolled during the pre-Delta, Delta, and Omicron periods respectively. Severe maternal adverse outcome was reported in 3.4% (n = 947/1402; 95% confidence intervals (95%CI) 2.5-4.5), 6.5% (n = 7/262; 95%CI 3.8-10.2), and 1.0% (n = 4/391; 95%CI 0.3-2.6) of women during the pre-Delta, Delta, and Omicron periods. The risk of severe maternal adverse outcome was higher during the Delta vs pre-Delta period (adjusted risk ratio (aRR) = 1.8; 95%CI 1.1-3.2) and lower during the Omicron vs pre-Delta period (aRR = 0.3; 95%CI, 0.1-0.8). The risks of hospitalization for COVID-19 were 12.6% (n = 176/1402; 95%CI 10.9-14.4), 17.2% (n = 45/262; 95%CI 12.8-22.3), and 12.5% (n = 49/391; 95%CI 9.4-16.2), during the pre-Delta, Delta, and Omicron period, respectively. Pregnancy complications occurred after SARS-CoV-2 exposure in 30.0% (n = 363/1212; 95%CI 27.4-32.6), 35.2% (n = 83/236; 95%CI 29.1-41.6), and 30.3% (n = 105/347; 95%CI 25.5-35.4) of patients during the pre-Delta, Delta, and Omicron periods, respectively. Stillbirths were reported in 0.5% (n = 6/1159; 95%CI 0.2-1.1), 2.8% (n = 6/210; 95%CI 1.0-6.0), and 0.9% (n = 2/213; 95%CI 0.1-3.4) or patients during the pre-Delta, Delta, and Omicron periods respectively. INTERPRETATION The Delta period was associated with a higher risk of severe maternal adverse outcome and the Omicron period with a lower risk of severe adverse outcome compared to pre-Delta era. The reported risk of hospitalization was high during the Omicron period and should not be trivialized. FUNDING Swiss Federal Office of Public Health, Fondation CHUV

Maternal outcomes and risk factors for COVID-19 severity among pregnant women.

Pregnant women may be at higher risk of severe complications associated with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which may lead to obstetrical complications. We performed a case control study comparing pregnant women with severe coronavirus disease 19 (cases) to pregnant women with a milder form (controls) enrolled in the COVI-Preg international registry cohort between March 24 and July 26, 2020. Risk factors for severity, obstetrical and immediate neonatal outcomes were assessed. A total of 926 pregnant women with a positive test for SARS-CoV-2 were included, among which 92 (9.9%) presented with severe COVID-19 disease. Risk factors for severe maternal outcomes were pulmonary comorbidities [aOR 4.3, 95% CI 1.9-9.5], hypertensive disorders [aOR 2.7, 95% CI 1.0-7.0] and diabetes [aOR2.2, 95% CI 1.1-4.5]. Pregnant women with severe maternal outcomes were at higher risk of caesarean section [70.7% (n = 53/75)], preterm delivery [62.7% (n = 32/51)] and newborns requiring admission to the neonatal intensive care unit [41.3% (n = 31/75)]. In this study, several risk factors for developing severe complications of SARS-CoV-2 infection among pregnant women were identified including pulmonary comorbidities, hypertensive disorders and diabetes. Obstetrical and neonatal outcomes appear to be influenced by the severity of maternal disease

Anticoagulation of women with congenital heart disease during pregnancy

Outcome of patients with congenital heart disease (CHD) has significantly improved over the last 40 years and most patients survive into adulthood. A considerable number of women with repaired and non-repaired CHD lesions reach the age of procreation. These patients encounter more frequently maternal and fetal complications during pregnancy than the general population. Pregnant patients with CHD are not only at a particularly elevated risk for thromboembolic events but also present a high predisposition for bleeding complications. Anticoagulation treatment during pregnancy with vitamin K antagonists (VKA) and low molecular weight heparin- (LMWH) significantly increases the already important risk for maternal and fetal adverse events in these women. Patients after mechanical heart valve prosthesis implantation are at highest risk. This article reviews the specific cardiac, obstetric and hemostasiologic aspects of pregnant women with CHD and anticoagulation treatment, and provides suggestions for the follow-up and possible anticoagulation strategies during pregnancy