Abstract MPWE29: Maternal Cardiovascular Disease Events Within Four Years of Delivery Following Pregnancy Complicated by COVID-19 Infection in 2020-2022.

Introduction: COVID-19 has been associated with increased risk during pregnancy and increased long-term cardiovascular disease (CVD) risk; however, few studies have examined CVD risk following pregnancy complicated by COVID-19. Therefore, our study assessed the pre-pregnancy and trimester-specific impact of COVID-19 on incident maternal CVD within four years of delivery in South Carolina (SC). Methods: We utilized SC vital records linked to hospitalization/emergency department records, and SC health department data on COVID-19 infections. COVID-19 exposure was defined as none, pre-pregnancy, during the 1 st or 2 nd trimester, or during the 3 rd trimester. CVD events were defined broadly based on ICD-10 codes: B33, G45.8, G45.9, I11, I13.0, I13.2, I20-I21, I24-I26, I30, I32, I40-I42, I44-I50, I51.4, I60-I67, I70-I72, I74, I75, I82, O87.1, O87.3, O90.3, R00.0, R00.1, R57.0. Women were followed from 7 days after delivery through 2023. Pregnancies were matched (on race/ethnicity, delivery quarter time, Medicaid eligibility, and maternal age), adjusted (for education, rural residence, smoking, firstborn, previous preterm delivery, and pre-pregnancy BMI, hypertension, and diabetes) and analyzed using a modified Poisson model. Cox proportional hazard models were also used in unmatched adjusted analyses. Results: Of 121,510 singleton deliveries to women aged 12-52 years f rom March 2020 through December 2022, 8.0% had a COVID-19 infection pre-pregnancy, 6.1% in the 1 st or 2 nd trimester, and 3.8% in the 3 rd trimester, and 3.0% had a CVD event. In matched analyses, COVID-19 infection during the 1 st and/or 2 nd trimester risk ratio (RR)=1.24, 95% CI: 1.05-1.45 increased the risk of CVD events compared to pregnancies without COVID-19 after adjustment. In contrast, COVID-19 infection pre-pregnancy (RR=0.93, 95% CI: 0.78-1.10) or during the 3 rd trimester (RR=0.93, 95% CI: 0.76-1.15) was not associated with increased risk of CVD. Cox proportional hazard model results were similar in unmatched adjusted analyses for COVID-19 infection during the 1 st or 2 nd trimester (hazard ratio (HR)=1.27, 95% CI: 1.11, 1.46), pre-pregnancy (HR=0.97, 95% CI: 0.83, 1.14) and during the 3 rd trimester (HR=0.95, 95% CI: 0.79, 1.13). Conclusion: Risk of CVD was elevated for pregnant women with COVID-19 infection during the 1 st or 2 nd trimester but not during the 3 rd trimester or pre-pregnancy, emphasizing the importance of preventive measures like vaccination to curb potential long-term risk.