Effects of prenatal opioid exposure on infant sympathetic and parasympathetic nervous system activity

Prenatal opioid exposure has been associated with developmental problems, including autonomic nervous system dysregulation. However, little is known about the effects of prenatal opioid exposure on the autonomic nervous system beyond the first days of life, particularly across both the parasympathetic and sympathetic branches, and when accounting for exposure to other substances. The present study examined the effects of prenatal exposure to opioid agonist therapy (OAT, e.g., methadone) and other opioids on infant autonomic nervous system activity at rest and in response to a social stressor (the Still-Face Paradigm) at six months among 86 infants varying in prenatal opioid and other substance exposure. Results indicated that OAT and other opioids have unique effects on the developing autonomic nervous system that may further depend on subtype (i.e., methadone versus buprenorphine) and timing in gestation. Results are discussed in the context of theoretical models of the developing stress response system. Prenatal opioid exposure (POE) is a major public health concern and impacts the fetal and neonatal autonomic nervous system (ANS). However, little is known about POE effects on the ANS beyond the neonatal period and accounting for other substance exposure. The present study describes the effects of POE on infant respiratory sinus arrhythmia and pre-ejection period at six months of age and the differential effects of type and timing of exposure in the context of polysubstance exposure.