Extended-release versus oral buprenorphine as opioid maintenance treatment during pregnancy-maternal and neonatal outcomes.

OBJECTIVE: To get information on subcutaneous extended-release buprenorphine as opioid maintenance treatment during pregnancy, we compared it to orally administered buprenorphine and buprenorphine-naloxone treatments. We hypothesized that maternal and neonatal outcomes do not differ between the treatment groups. Study design In this population-based cohort study, 60 pregnant individuals receiving non-changed opioid maintenance treatment for opioid use disorder with a buprenorphine product from the time before conception to the time after delivery and their newborns were included. They were divided into three groups based on the pharmacotherapy with subcutaneous extended-release buprenorphine, sublingual buprenorphine, or buprenorphine-naloxone. Statistical analyses were conducted using Fischer's exact tests, ANOVA tests, and Kruskal-Wallis tests. All the statistical tests were two-tailed.

RESULTS: The frequency of pregnancy or delivery complications did not significantly differ between the group receiving extended-release buprenorphine and the other groups. During pregnancy, 38 % of the women used illicit drugs concomitantly, with equal frequency in the extended-release buprenorphine group and the other groups. Of the neonates, 93 % were born full-term and 90 % got at least eight Apgar points in one minute age, without significant differences between the groups (p = 0.57). The need for pharmacotherapy for neonatal opioid withdrawal syndrome was the lowest in the extended-release buprenorphine group (25 %) and highest in the sublingual buprenorphine group (67 %). Still, the difference between the treatment groups did not reach statistical significance (p = 0.17). Among all neonates, the breastfed infants were less likely to receive pharmacotherapy for withdrawal symptoms than the formula-fed ones (p = 0.048).

CONCLUSIONS: Extended-release buprenorphine with steady drug concentration seems to be a promising pharmacotherapy option during pregnancy for mothers. Maternal health during pregnancy may contribute to the well-being of newborns. Larger trials are urgently needed to confirm these results..