Naltrexone Treatment for Pregnant Women With Opioid Use Disorder Compared With Matched Buprenorphine Control Subjects

The use of the opioid antagonist naltrexone (NTX) for pregnant women with opioid use disorder (OUD) remains understudied. The purpose of this pilot study was to examine pregnancy and neonatal outcomes in a cohort of NTX-treated women.

This single-center, retrospective cohort study included 6 mother-infant dyads taking NTX compared with 13 taking buprenorphine (BUP) between 2017 and 2019. Maternal demographic characteristics, any unprescribed or illicit opioid use per urine toxicology or provider report during the pregnancy or 6 months' postdelivery, delivery outcomes, gestational age, birth weight, Apgar scores, neonatal intensive care unit admission, and neonatal abstinence syndrome (NAS) outcomes (NAS diagnosis, pharmacologic treatment, and total hospital length of stay) were compared.

Maternal and infant demographic characteristics were similar between the 2 groups, with the exception of cigarette smoking in the BUP group being more common (92% vs 33%; P = 0.02). None of the women on NTX versus 23% of the women on BUP had documented opioid misuse (P = 0.52). No infants in the NTX group had a NAS diagnosis versus 92% in the BUP group (P < 0.001). Forty-six percent of the BUP-exposed infants were treated for NAS versus 0% in the NTX group (P < 0.001). NTX-exposed infants had a shorter length of stay (mean [SD], 3.2 [1.6] vs 10.9 [8.2] days; P = 0.008).

Maintaining women on NTX during pregnancy was associated with favorable outcomes. These results support the need for larger multicenter studies sufficiently powered to detect possible differences between the medications on long-term maternal and child safety and efficacy outcomes.