Lesion-specific recurrence patterns of congenital heart disease in subsequent pregnancies: nationwide cohort study

초록

Objectives: To evaluate recurrence patterns of CHD with a focus on lesion-specific recurrence and the association with maternal prepregnancy body mass index (BMI). Methods: This nationwide cohort study included women with two singleton births between 2015 and 2021 whose first offspring had CHD. The outcome was CHD recurrence in the second offspring. CHD subtypes were classified into septal defects, conotruncal defects, left-sided obstructive lesions, atrioventricular septal defects (AVSD), and complex CHD. CHD severity was categorized as minor (septal defects) or major (all other subtypes). Adjusted risk ratios were estimated using multivariable regression models controlling for maternal age, interpregnancy interval, hypertension, diabetes, and CHD subtype. BMI analyses were restricted to women with prepregnancy BMI data and included categorical and continuous models with splines for non-linearity. Results: Among 8,886 women with a first offspring affected by CHD, 1,014 (10.5%) experienced recurrence. Same-lesion recurrence (8.21%) was more frequent than cross-lesion recurrence (2.31%). Recurrence patterns were lesion-specific, with the highest concordance in septal defects (aRR 1.89, 95% CI 1.26–2.84); cross-lesion recurrence remained uncommon. When stratified by severity, recurrence was higher in minor CHD (aRR 1.76), but not in major CHD (aRR 1.11). In BMI-restricted analyses (n = 2,439), maternal BMI was not independently associated with CHD recurrence. Overweight and obesity showed non-significant trends toward increased risk (aRR 1.44 and 1.40, respectively), and no significant associations were observed in continuous or spline analyses. Conclusions: CHD recurrence showed lesion-specific patterns with predominant same-lesion recurrence, suggesting shared developmental mechanisms. Maternal prepregnancy BMI was not significantly associated with recurrence risk. These findings support defect-specific counseling and suggest that intrinsic biological susceptibility may play a greater role than maternal metabolic factors in CHD recurrence.