Maternal Cardiac and Perinatal Outcomes Among Pregnant Individuals With Ebstein's Anomaly.

Ebstein's anomaly is a rare congenital cardiac condition with limited data regarding the impact of this condition in pregnancy. The objective of this study was to describe the cardiac and perinatal outcomes associated with Ebstein's anomaly in pregnancy. We performed a retrospective cohort of pregnancies from Epic Cosmos, an integrated dataset from over 1,500 hospitals across the United States. Charts were queried for the coexistence of pregnancy and Ebstein's anomaly diagnosis code between July 5, 2021, and March 5, 2025. They were then compared to patients with other congenital heart disease by ICD-10 code and patients with no history of congenital heart disease. Patients with Ebstein's anomaly were also then further stratified by cardiac arrhythmia status. Demographics and clinical characteristics were abstracted and compared utilizing student t-test, ANOVA, or Chi-square where appropriate. During the study period, 261 individuals with maternal Ebstein's anomaly and pregnancy were identified. They were compared to 20,746 pregnant patients with other congenital heart disease and 5,048,035 pregnant patients with no history of Ebstein's congenital heart disease. There were statistically significant differences by age, race, ethnicity, and body mass index across all 3 groups. There were also statistically significant differences in cardiac outcomes of arrhythmia and heart failure and perinatal outcomes of gestational age of at delivery and mode of delivery across groups. Approximately 41% of pregnant individuals with Ebstein's anomaly developed a cardiac arrhythmia, while 18.4% developed heart failure. In conclusion, Ebstein's anomaly is associated with significant cardiac risks in pregnancy, including cardiac arrhythmia and heart failure.