Maternal buprenorphine treatment during pregnancy and maternal physiology

Background: Buprenorphine, used for opioid use disorder (OUD) treatment during pregnancy, provides unknown effects on maternal physiological activity. The primary aim of this report is to document acute effects of buprenorphine administration on indicators of maternal autonomic functioning. Effects of maternal buprenorphine dose and other substance exposures on maternal measures were examined, as were neonatal abstinence syndrome (NAS) outcomes. Methods: Forty-nine pregnant, buprenorphine-maintained women yielded maternal physiologic information (heart rate and variability, electrodermal activity, and respiratory rate) at 24, 28, 32 and 36 weeks gestation. Monitoring at trough and peak maternal medication levels was implemented to ascertain acute physiologic effects of buprenorphine administration. Results: Buprenorphine administration accelerated maternal heart rate and reduced variability at two gestational ages (24 and 36 weeks) and suppressed sympathetic (electrodermal) activation at 24, 28 and 32 weeks at times of peak maternal medication levels. Maternal autonomic parameters were unrelated to polysubstance exposure with the exception of cigarette smoking. Heavier smoking dampened maternal heart rate variability across gestation and potentiated reactivity to buprenorphine at 24 and 36 weeks. Heavier smoking was also associated with reduced electrodermal activity at 36 weeks. Buprenorphine dose was unrelated to observed effects. Larger degree of maternal heart rate reactivity to buprenorphine administration was related to more severe NAS expression. Conclusions: These findings detail the maternal autonomic response to buprenorphine administration but also illustrate the significant effect of concurrent cigarette use on maternal autonomic regulation. This suggests the importance of smoking-reduction strategies in the comprehensive, medication-assisted treatment of women with OUD.