Cesarean delivery volume and risk of long-term neurodevelopmental disorders in offspring

Institutional procedure volume has been linked to surgical morbidity and mortality, but its impact on long-term child neurodevelopment following cesarean delivery is unknown.

This retrospective, nationwide cohort study utilized South Korean National Health Insurance Service data. Cesarean births from 2010 to 2014 (n = 735 280) were followed through to 2023. Hospitals were categorized into annual volume quartiles: Q1 (≤185), Q2 (186-356), Q3 (357-600), and Q4 (>600). Multivariable Cox proportional hazards models, adjusted for maternal and obstetric covariates, estimated adjusted hazard ratio (aHR) with 95% confidence intervals (CIs) for long-term neurodevelopmental disorder (LNDD).

Over a mean follow-up period of 12.4 years, LNDD was diagnosed in 31 041 children (4.2%). The incidence rates of LNDD were 3.8, 3.6, 3.1, and 3.4 per 1000 person-years for Q1, Q2, Q3, and Q4, respectively. Compared with Q1, the adjusted hazard of LNDD was 0.97 (95% CI, 0.94-0.99; P = 0.044) in Q2, 0.85 (95% CI, 0.82-0.88; P < 0.001) in Q3, and 0.90 (95% CI, 0.88-0.94; P < 0.001) in Q4. Similar inverse associations were observed for intellectual disabilities (aHRs 0.93, 0.82, and 0.83 across Q2-Q4) and for disorders of psychological development (aHRs 0.97, 0.86, and 0.92; all P < 0.001 except Q2).

Hospital volume above the lowest quartile was independently associated with lower offspring LNDD hazard. The absence of a linear dose-response among higher quartiles suggests a plateau effect, emphasizing the need to optimize institutional readiness in low-volume settings to safeguard neurodevelopment.