Intrauterine exposure to maternal opioid maintenance treatment and associated risk factors may impair child growth

Abstract

AimHow maternal opioid maintenance treatment (OMT) affects children is under‐researched. This population‐based registry study investigated child growth and somatic health following intrauterine exposure to this treatment.MethodsChildren born between 1 March 2011 and 30 May 2021 to mothers who used buprenorphine, buprenorphine‐naloxone, or methadone throughout their pregnancies were followed for 2 years at the Helsinki University Hospital, Finland. Appropriate statistical tests were used to compare the treatment groups.ResultsOf the 67 neonates, 52% were male, 96% were born full‐term and 63% were treated for neonatal opioid withdrawal syndrome. Otherwise, the children were predominantly healthy, although relatively small: 22% were small for gestational age, the methadone group children being the smallest. Foetal exposure to maternal methadone treatment, illicit drugs, hepatitis C and smoking were associated with small for gestational age; the former two were also associated with later slower growth, especially head growth and weight gain (p < 0.001). However, 29% were overweight at 2 years.ConclusionUsing child growth as the outcome, we found that buprenorphine‐naloxone and buprenorphine‐monotherapy had equal effects as forms of maternal OMT. Exposure to multiple risk factors may harm foetal and subsequent growth. We recommend long‐term follow‐up of children exposed to maternal OMT.