Infections and obstetric outcomes in opioid-dependent pregnant women maintained on methadone or buprenorphine

Aims To characterize infections and compare obstetric outcomes in opioid-dependent pregnant women who participated in a randomized clinical trial comparing agonist medications, methadone and buprenorphine. Design Incidence of infections was identified as part of the screening medical assessment. As part of a planned secondary analysis, analysis of variance and polytomous logistic regressions were conducted on obstetric outcome variables using treatment randomization condition (maternal maintenance with either methadone or buprenorphine) as the predictor variable, controlling for differences between study sites. Setting Six United States sites and one European site that provided comprehensive treatment to opioid-dependent pregnant women. Participants Pregnant opioid-dependent women (n=131) who delivered while participating in the Maternal Opioid Treatment: Human Experimental Research (MOTHER) study. Measurements Obstetric, infectious and other maternal medical complications captured by medical records, physical examination, blood tests and self-report. Neonatal medical complications captured by medical records. Findings Hepatitis C was the most common infection (32.3%), followed by hepatitis B (7.6%) and chlamydia (6.1%) among participants at study enrollment. Maternal methadone versus buprenorphine maintenance was associated with a higher incidence of preterm labor (P=0.04) and a significantly higher percentage of signs of respiratory distress in neonates at delivery (P=0.05). Other medical and obstetric complications were infrequent in the total sample, as well as in both methadone and buprenorphine conditions. Conclusions Buprenorphine appears to have an acceptable safety profile for use during pregnancy.