Aims: To assess neonatal abstinence syndrome (NAS) and neurodevelopmental outcome in infants born to addicted mothers under buprenorphine substitution therapy.
Setting: District general hospital, Angoulême, France.
Methods: Retrospective case records study of infants admitted to the neonatal intensive care unit (NICU) and/or special care baby unit (SCBU) from January 1994 to December 2000 for surveillance and/or treatment of buprenorphine NAS.
Results: Thirteen infants were born to addicted mothers under buprenorphine maintenance therapy during the study period. Eight were male and five were female; mean birth term and weight were 39 weeks gestation and 3000 g, respectively. Apgar scores were within normal limits; four infants were small for gestational age, none was dysmorphologic and none was extracted for fetal distress. NAS occurred in 11 cases (85%) and required treatment in 10 cases. Morphine chlorhydrate 0.5 mg/kg/day was administered in divided doses to seven children and gave better results than paregoric alone or in combination with diazepam. Upon follow-up, seven children presented transient lower limbs hypertonia, jerky movements and jitteriness that lasted 3-9 months. The overall milestones acquisitions were within normal limits.
Conclusion: Buprenorphine substitution seems to be safe during pregnancy, and has had no teratogenic effects reported to date. It induces NAS of variable intensity that is less prolonged in comparison to methadone; the neurodevelopmental outcome of exposed children is normal in the majority of cases, although some presented with transient motor abnormalities that resolved completely in 85% of those recruited to our study.