Changes in adverse maternal, pregnancy, and delivery outcomes among U.S. delivery hospitalizations during the COVID-19 Pandemic, 2019-2020

Abstract Background Early reports suggested changes in select pregnancy outcomes during the coronavirus disease 2019 (COVID-19) pandemic. The population-level impact of the pandemic on pregnancy and delivery outcomes is not well understood. Objective To assess whether pregnancies that ended during the pandemic were at increased or decreased risk of selected adverse outcomes compared to the previous year. Methods Data from a cohort of delivery hospitalizations occurring during April-December of 2019 and 2020 in the Premier Healthcare Database were analyzed. Prevalence of select adverse outcomes were examined. Adjusted prevalence ratios (aPR) and 95% confidence intervals (CI) were estimated using Poisson regression with robust standard errors. Results We identified 663,620 deliveries occurring April-December of 2019 and 614,093 deliveries occurring April-December of 2020. We observed an increase in in-hospital death from 2019 to 2020 (n=33; 5 per 100,000 vs. n=53; 9 per 100,000, aPR: 1.68, CI: 1.09, 2.59), which was no longer statistically significant after excluding deliveries with a COVID-19 diagnosis (aPR: 1.25, CI: 0.78, 2.00). Intensive care unit admission decreased from 2019 to 2020 (n=10,964; 1.7% vs. n=9,480; 1.5%, aPR: 0.90, CI: 0.87, 0.92). Preterm birth decreased from 2019 to 2020 (n=61,101; 9.2% vs. n=56,158; 9.1%, aPR: 0.96, CI: 0.95, 0.97). The prevalence of cesarean deliveries was similar in 2019 and 2020 (30.9% vs 31.6%, respectively), but there were some differences in cesarean delivery characteristics (e.g., an increase in cesarean deliveries due to conduct of labor [n=2,553; 1.2% vs. n=2,642; 1.4%, aPR: 1.11, CI: 1.05, 1.17]) from 2019 to 2020. Conclusions In 2020 compared to 2019, in-hospital deaths among pregnant women increased and there was a small decrease in prevalence of preterm births. The full impact of the COVID-19 pandemic on maternal and pregnancy outcomes remains to be understood. However, it appears that most outcomes investigated experienced minimal change from 2019 to 2020.