Severe Acute Respiratory Syndrome Coronavirus 2 and Pregnancy Outcomes According to Gestational Age at Time of Infection

Abstract

We conducted an international multicenter retrospective cohort study, PregOuTCOV, to examine the effect of gestational age at time of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on obstetric and neonatal outcomes. We included all singleton pregnancies with a live fetus at 10 weeks' gestation in which pregnancy outcomes were known. The exposed group consisted of patients infected with SARS-CoV-2, whereas the unexposed group consisted of all remaining patients during the same period. Primary outcomes were defined as composite adverse obstetric outcomes and composite adverse neonatal outcomes. Of 10,925 pregnant women, 393 (3.60%) were infected with SARS-CoV-2 (exposed group). After matching for possible confounders, we identified statistically significant increases in the exposed group of composite adverse obstetric outcomes at >20 weeks' gestation and of composite adverse neonatal outcomes at >26 weeks' gestation (p<0.001). Vaccination programs should target women early in pregnancy or before conception, if possible.

Keywords: COVID-19; Europe; PregOuTCOV; SARS-CoV-2; coronavirus disease; high-risk pregnancy; pregnancy outcomes; propensity score matching; respiratory infections; severe acute respiratory syndrome coronavirus 2; vaccination; viruses; zoonoses.

Figure 1

Flowchart of the study population in PregOutCOV study of pregnancy outcomes in Europe according to gestational age at time of infection with severe acute respiratory syndrome coronavirus 2. Pregnancy losses before delivery were excluded from the neonatal population. WG, weeks of gestation.

Figure 2

Kaplan-Meier curves demonstrating the effect of gestational age at the time of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on pregnancy outcomes in Europe. A) Compared with patients without CAOO, patients with CAOO were more often infected with SARS-CoV-2. The difference was seen when patients were infected at >20 weeks of gestation. B) Compared with patients without CANO, patients with CANO were more often infected with SARS-CoV-2. The difference was seen when patients were infected at >26 weeks of gestation. Numbers below x-axis indicate number of persons at risk for each time point. CANO, composite adverse neonatal outcome; CAOO, composite adverse obstetric outcome.