Small for gestational age in twin pregnancies and the risk of offspring pediatric neurologic morbidity

Small for gestational age (SGA) singletons are at increased risk for neurodevelopmental abnormalities. Scarce data exist regarding the long-term implications of SGA in twins. We opted to study the association between SGA of one twin and long-term neurologic related morbidity in dichorionic diamniotic twins.

A population-based retrospective cohort study including consecutive dichorionic diamniotic twins, born between the years 1991 and 2021 at a tertiary medical center was conducted. Total and subtypes of neurologic related pediatric hospitalizations among SGA versus non-SGA twins were compared. A Kaplan–Meier survival curve was used to compare the cumulative neurologic morbidity incidence, and a Cox proportional hazards model was constructed to adjust for confounders.

The study population included 4222 newborns; 180 (4.3%) were SGA. Rate of long-term neurologic related hospitalizations was comparable between the two groups (8.7 vs. 8.0%, p = 0.755; Kaplan–Meier survival curve Log-rank p = 0.652). Using a Cox proportional hazards model, controlling for gender and birth order, no association was found between SGA and the risk for subsequent neurologic pediatric morbidity of the offspring (Adjusted HR = 1.0, 95% CI 0.6–1.8, p = 0.973).

SGA is not associated with an increased risk for long-term pediatric neurologic morbidity in dichorionic diamniotic twins.