Survival of children with congenital heart defects (CHD) has improved substantially, but recent studies suggest a plateau, and the contribution of changes in prenatal diagnosis and termination of pregnancy for fetal anomaly (TOPFA) remains unclear.

To assess long-term trends in one-year survival among infants with CHD and in TOPFA, and the extent to which changes in TOPFA may explain survival trends, separately for isolated and non-isolated CHD.

We conducted a population-based study using data from the Paris Registry of Congenital Anomalies (1994–2023). Isolated CHD were defined as CHD without associated genetic or extracardiac anomalies, as opposed to non-isolated CHD. One-year survival among live-born infants was estimated using Kaplan–Meier methods. Temporal trends in survival and TOPFA were analyzed using logistic regression, with assessment of non-linearity (fractional polynomials) and slope changes (segmented models).

Among 5674 CHD cases, 66.1% were isolated and 33.9% were non-isolated; 4210 were live births, 1325 TOPFA and 139 stillbirths. One-year survival was 90.9% (95% CI 89.9–91.7), reaching 95.0% in isolated CHD and 76.3% in non-isolated CHD ( P < 0.001). Survival improved over time with a non-linear pattern, with annual gains declining from 0.6–0.7% before the late 2000s to 0.1–0.2% thereafter. This improvement was driven by isolated CHD, in which survival increased despite a decline in TOPFA. In contrast, in non-isolated CHD, both survival and TOPFA rates remained stable over time.

Survival of infants with CHD improved over time but was confined to isolated defects, with no meaningful progress in non-isolated CHD. Divergent trends between survival and TOPFA challenge the notion of a plateau and argue against prenatal selection as the primary driver of recent survival patterns.