SARS-CoV-2 infection during pregnancy and associated perinatal health outcomes: a national US cohort study

Abstract

Abstract Background SARS-CoV-2 infection has been associated with increased risk of adverse perinatal health outcomes. However, few large-scale, community-based epidemiological studies have been conducted. Methods We conducted a national cohort study using de-identified administrative claims data for 78,283 pregnancies with estimated conception before 30 April 2020 and pregnancy end after 11 March 2020. We identified maternal infections using diagnostic and laboratory testing data. We compared the risk of pregnancy outcomes using Cox proportional hazard models treating COVID-19 as a time-varying exposure and adjusting for baseline covariates. Results 2,655 (3.4%) pregnancies had a documented SARS-CoV-2 infection; 3.4% required admission to intensive care, invasive mechanical ventilation or ECMO treatment. COVID-19 during pregnancy was not associated with risk of miscarriage, antepartum hemorrhage, or stillbirth, but was associated with 2-3 fold higher risk of induced abortion (adjusted hazard ratio [aHR] 2.60, 95% CI 1.17-5.78), c-section (aHR 1.99, 95% CI 1.71-2.31), clinician-initiated preterm birth (2.88; 95% CI 1.93, 4.30), spontaneous preterm birth (aHR 1.79, 95% CI 1.37-2.34), fetal growth restriction (aHR 2.04, 95% CI 1.72-2.43), and postpartum hemorrhage (aHR 2.03, 95% CI 1.6-2.63). Conclusions Prenatal SARS-CoV-2 infection was associated with increased risk of adverse pregnancy outcomes. Prevention could have fetal health benefits.