361: Neonatal head circumference in opioid-exposed neonates with and without Neonatal Opioid Withdrawal Syndrome (NOWS)

Abstract

Neonates born with NOWS may have smaller brain volumes and also have been reported to have smaller head circumferences compared to non-opioid exposed controls. There is limited data, however, comparing head measurements in neonates with NOWS versus those exposed to opioids who do not develop NOWS. The study objective was to evaluate whether opioid exposure during pregnancy was associated with an increased frequency of abnormal head measurement and whether symptomatic newborns requiring treatment had different head biometry compared to those not requiring treatment. We performed a retrospective cohort study of pregnant women with a singleton gestation diagnosed with opioid use disorder (OUD) and receiving buprenorphine for medication-assisted treatment (MAT) at a tertiary care academic institution from April 2015 to March 2018. We compared characteristics for newborns treated for NOWS with those not requiring medication. Data collection included head circumference (HC) at birth, demographics, illicit substances, toxicology studies, newborn gender, birth weight, and medical comorbidities. All statistical analyses were performed using SAS 9.4. 173 cases were included in the analysis. The incidence of NOWS was 39.9% (n=69) in our cohort. There was no statistical significant difference in HC among neonates treated for NOWS (33.4 ± 0.3 cm) and those not treated for NOWS (33.4 ± 0.3 cm). There was no statistical difference in neonatal gender, smoking status, hypertensive disease in pregnancy, or diabetes between the two groups. Of the 173 opioid-exposed neonates, only 15 (8.7%) had a head circumference less than the 10th percentile. Our data found neonates that develop medication-requiring NOWS do not have a smaller head circumference as compared to opioid-exposed controls. The low incidence for low head circumference does not support the observation these neonates are at marked risk for abnormal brain volumes when enrolled in a comprehensive, multidimensional treatment program.