ABSTRACT
Background Pregnant individuals are at increased risk of COVID-19 hospitalization and death, and primary and booster COVID-19 vaccination is recommended for this population. Methods Among a cohort of pregnant individuals who received prenatal care at three healthcare systems in the United States, we estimated the cumulative incidence of hospitalization with symptomatic COVID-19 illness. We also identified factors associated with COVID-19 hospitalization using a multivariable Cox proportional-hazards model with pregnancy weeks as the timescale and a time-varying adjustor that accounted for SARS-CoV-2 circulation;model covariates included site, age, race, ethnicity, insurance status, pre-pregnancy weight status, and selected underlying medical conditions. Data were collected primarily through medical record extraction. Results Among 19,456 pregnant individuals with an estimated due date March 1, 2020-February 28, 2021, 75 (0.4%) were hospitalized with symptomatic COVID-19. Factors associated with hospitalization for symptomatic COVID-19 were Hispanic ethnicity (aHR: 2.7;95% CI: 1.3,5.5), native Hawaiian or Pacific Islander race (aHR: 12;95% CI: 3.2,45.5), age <25 years (aHR: 3.1;95% CI: 1.3,7.6), pre-pregnancy obesity (aHR: 2.1;95% CI: 1.1,3.9), diagnosis of a metabolic disorder (aHR: 2.2;95% CI: 1.2,3.8), lung disease excluding asthma (aHR: 49;95% CI: 28,84) and cardiovascular disease (aHR: 2.6;95% CI: 1.5,4.7). Conclusion Although hospitalization with symptomatic COVID-19 was uncommon, pregnant individuals should be aware of risk factors associated with severe illness when considering COVID-19 vaccination.