Prenatal methadone exposure and neonatal neurobehavioral functioning.

Opioid-exposed infants display a wide and variable range of dysregulated neurobehavioral functioning, but the regulatory difficulties experienced by these infants outside the defined clusters of neonatal abstinence syndrome (NAS) have not been well described and may have implications for the infant's developmental course. This study describes the neurobehavioral functioning of neonates prenatally exposed to methadone, using the NICU Network Neurobehavioral Scale (NNNS), and explores the relationships between maternal factors and infant functioning. The relationship between NNNS measures, NAS severity, and need for pharmacotherapy for NAS was also evaluated. Infants who required pharmacologic treatment for NAS showed more dysregulated behavior and signs of stress and abstinence as indicated by NNNS scores, but NNNS scores were not significantly correlated with maternal methadone dose. The determination of the range of the methadone-exposed infant's neurobehavioral repertoire could guide the optimal treatment of all such infants, particularly those requiring only nonpharmacologic care.