Prenatal buprenorphine/naloxone exposure and neonatal neurobehavioral functioning: A preliminary report

Although prescription of buprenorphine/naloxone during pregnancy is gaining acceptance, buprenorphine monotherapy is more often used due to the scarce knowledge of the effects of the combined medications on the fetus and neonate. Evaluation of neurobehavioral functioning of neonates prenatally exposed to buprenorphine/naloxone is lacking. The NICU Network Neurobehavioral Scale (NNNS) has been used to evaluate neurobehavioral functioning, stress responses, and regulatory capacities of neonates at risk for altered development due to prenatal stressors. This pilot study presents a descriptive analysis of the neurobehavioral functioning among neonates exposed in utero to buprenorphine/naloxone, as well as maternal characteristics and factors present during their pregnancy.

Participants were pregnant parents receiving comprehensive treatment for opioid use disorder (OUD) and obstetric care, choosing buprenorphine/naloxone treatment with singleton, uncomplicated pregnancies. Participants provided confidential urine specimens for legal and illegal psychoactive substances according to protocol. Maternal psychiatric disorders and psychiatric medications as well as weekly dosing records were obtained for the duration of study participation. The NNNS was administered to 16 full-term neonates on days 3,14 and 30 of life.

Mean summary scores for 12 neurobehavioral domains (attention, arousal, self-regulation, handling, quality of movement, excitability, lethargy, non-optimal reflexes, asymmetrical reflexes, hypertonia, hypotonia and stress/abstinence syndrome) are presented for neonates prenatally exposed to buprenorphine/naloxone at three time points during the first month of life. Several maternal factors that can influence the functioning of the neonate were presented in this sample including smoking cigarettes (94 %), a psychiatric diagnosis (87.5 %), positive urinalysis for legal or illegal substances during treatment (56.2 %).

This report provides preliminary information regarding the neurobehavioral functioning of neonates exposed to buprenorphine/naloxone over the first month of life, including consideration of maternal factors. However, future research with a larger sample and controlling for different neonate and maternal factors is necessary to confirm these preliminary findings.