Abstract Objective This study aimed to evaluate the incidence and characteristics of severe adverse cardiac events (SCEs) in pregnant women with congenital heart disease (CHD), and to determine the proportion and contributing factors of preventable events. Methods We retrospectively reviewed the medical records of pregnant women with CHD who delivered at Songklanagarind Hospital between January 1, 2006, and December 31, 2024. Pregnancies with an invalid diagnosis, missing essential data, or loss to follow‐up before delivery or termination were excluded. Collected data included baseline clinical and cardiac characteristics, SCEs, obstetric complications, and factors contributing to preventable failures. Results During the 19‐year period, SCEs occurred in 24.7% (85 of 344) of pregnancies, including six maternal deaths (1.7%). The most common event was deterioration of New York Heart Association functional class by ≥2 levels, followed by congestive heart failure. Most cases (87.1%, 74 of 85) were considered preventable, with contributing factors related to both patients and healthcare providers. Conclusion The incidence of SCEs in pregnancies with CHD was high, with the majority deemed preventable.
Peeyananjarassri et al. (2026) studied this question.