(250) Impact of COVID-19 on Pregnancy Complications & Outcomes in The Healthcore Integrated Research Database

Publication Number: 581

Background: There is increasing evidence that maternal COVID-19 infection increases the risk of pregnancy complications and adverse pregnancy outcomes. The HealthCore Integrated Research Database (HIRD) contains claims from approximately 1 in 10 US pregnancies during the pandemic, presenting a unique opportunity to study the effects of COVID-19 on pregnancy.

Objectives: To utilize data from a large health insurance claims database to investigate the effect of COVID-19 infection on pregnancy-related outcomes.

Methods: We included women with an ICD-10-CM or ICD-10-PCS code for a pregnancy outcome during the study period (Jan 2020 – Mar 2021), with 6 months of continuous enrollment in the HIRD prior to their estimated last menstrual period (LMP) date, and aged 18-49 years at LMP. We restricted women to their first pregnancy. Maternal COVID-19 status was determined using ICD-10-CM U07.1 for lab-confirmed COVID-19 or a positive antigen or RNA test any time during or 30 days prior to LMP. We calculated the prevalences of preterm birth, stillbirth, small for gestational age (SGA), low birth weight (LBW), pre-eclampsia, eclampsia, gestational hypertension, caesarian delivery, and major congenital malformations (MCM) among COVID-19 infected and non-COVID-19 infected pregnancies. We calculated unadjusted prevalence ratios (PRs) and 95% confidence intervals (CI) for each outcome, comparing COVID-19 infected to uninfected pregnancies.

Results: We identified 188,072 qualifying pregnancies during the study period. Of these, 8,920 (5%) were exposed to documented maternal COVID-19 infection. We observed higher prevalences for all examined birth outcomes among COVID-19 pregnancies as compared to non-COVID pregnancies, with PRs ranging from 1.10 to 1.99: stillbirth: 1.10 (95% CI: 0.91-1.34); preterm birth: 1.24 (95% CI 1.14-1.36); SGA: 1.25 (95% CI: 1.17-1.33); pre-eclampsia: 1.45 (95% CI:1.36-1.55); gestational hypertension: 1.28 (95% CI:1.21-1.35); C-section: 1.21 (95% CI: 1.17-1.25); and MCM: 1.26 (95% CI: 1.01-1.57) eclampsia: 1.99 (95% CI:1.32-2.99).

Conclusions: Pregnancy complications and adverse pregnancy outcomes were more common among pregnancies with documented maternal COVID-19 infection. These relations will be further explored through propensity score-based weighting to adjust for clinical and demographic confounders, and through bias analyses to account for changes in COVID-19 testing over time. Covariate-adjusted PRs and sensitivity analyses to account for potential exposure misclassification and calendar time bias are in progress. Future analyses will account for vaccination as part of the increasing complexity of examining the effects of maternal COVID-19 on pregnancy.