Preterm infants, born at 35-36 weeks, are often admitted to a level I unit (well-newborn maternity wards). However, they may still be physiologically immature.
Infants born late preterm have a higher risk of neonatal mortality than their term (37-41 weeks) counterparts. Additionally, they also have a higher risk of neonatal morbidity, with an increased health care burden. This risk in infants born at 35-36 weeks compared with term infants is yet to be studied briefly on a national population level.
A recent study assessed the risk for neonatal morbidities among infants born late preterm at 35-36 gestational weeks, early term (37-38 weeks), and late-term (41 weeks) infants, compared with full-term (39-40 weeks) infants.
This nationwide population-based cohort study was carried out in 1,650,450 non-malformed liveborn singleton infants born at 35-41 weeks between 1998 and 2016 in Sweden. The relative risks for low Apgar score (0-3) at 5 minutes; respiratory, metabolic, infectious, and neurologic morbidities; and severe neonatal morbidity (composite outcome) were adjusted for maternal, pregnancy, delivery, and infant characteristics.
The results were as follows-
Thus, infants born late preterm at 35-36 weeks of gestation possess a greater risk of neonatal morbidities, however, the absolute risks for severe neonatal morbidities are low. Hence there is a need of preventing late preterm delivery to decrease the burden of neonatal morbidity and help professionals and families with a better risk assessment.
Source: Mitha A, Chen R, Altman M, Johansson S, Stephansson O, Bolk J. Neonatal Morbidities in Infants Born Late Preterm at 35-36 Weeks of Gestation: A Swedish Nationwide Population-based Study. The Journal of Pediatrics. 2021;233:43-50. DOI:https://doi.org/10.1016/j.jpeds.2021.02.066