Risk factors for neonatal encephalopathy in late preterm and term singleton births in a large California birth cohort.

Objective: The objective was to investigate maternal and pregnancy characteristics associated with neonatal encephalopathy (NE).

Study Design: We queried an administrative birth cohort from California between 2011 and 2017 to determine the association between each factor and NE with and without hypothermia treatment.

Results: From 3 million infants born at 35 or more weeks of gestation, 6,857 cases of NE were identified (2.3 per 1000 births), 888 (13%) received therapeutic hypothermia. Risk factors for NE were stronger among cases receiving hypothermia therapy. Substance-related diagnosis, preexisting diabetes, preeclampsia, and any maternal infection were associated with a two-fold increase in risk. Maternal overweight/obesity, nulliparity, advanced maternal age, depression, gestational diabetes or hypertension, and short or long gestations also predicted NE. Young maternal age, Asian race and Hispanic ethnicity, and cannabis-related diagnosis lowered risk of NE.

Conclusions: By disseminating these results, we encourage further interrogation of these perinatal factors.