Early neonatal transfers after moderate and late preterm birth: a nationwide cohort study based on the French National Health Data System

To investigate how level of maternity unit and clinical risk factors influence early neonatal transfer among moderate and late preterm (MLP; 32–36 weeks’ gestation (WG)) infants. We conducted a nationwide cohort study including all liveborn MLP infants in France between 2014 and 2021. Infants with congenital malformations, stillbirths, and out-of-hospital births were excluded. Neonatal transfers within 48 h after birth, with death before 48 h as a competing event, were analyzed by gestational age, maternity level (I/IIa/IIb/III) and major clinical risk groups, including multiple pregnancy, small for gestational age (SGA) and/or fetal growth restriction (FGR) and maternal pregnancy complications. Among 309,062 MLP infants, 6.7% were transferred (6.5%) or died (0.2%). Transfer rates declined by gestational age from 14.7% at 32 weeks to 3.4% at 36 WG. Transfers were most frequent in level I (19.0%) and IIa (9.5%) units, compared with level IIb (3.5%) and III (3.0%) units. Clinical risk, particularly SGA/FGR, was associated with high transfer rates in level I and II units, even at later gestations (88.2% at 34 WG and 33.1% at 36 WG in level I units). Variability in transfer rates in subgroups of MLP infants highlights the need for risk-stratified regionalization policies.