Outcomes associated with the use of medications for opioid use disorder during pregnancy.

AIM

To test the effect of the duration of medication for opioid use disorder (MOUD) use during pregnancy on maternal, perinatal and neonatal outcomes.

DESIGN

Retrospective cohort analysis of claims, encounter and pharmacy data.

SETTING

Pennsylvania, USA.

PARTICIPANTS

We analyzed 13 320 pregnancies among 10 741 women with opioid use disorder aged 15-44 years enrolled in Pennsylvania Medicaid between 2009 and 2017.

MEASUREMENTS

We examined five outcomes during pregnancy and for 12 weeks postpartum: (1) overdose, (2) postpartum MOUD continuation, (3) preterm birth (< 37 weeks gestation), (4) term low birth weight (< 2500 g at ≥ 37 weeks) and (5) neonatal abstinence syndrome (NAS). Our primary exposure was the duration (count of weeks) of any MOUD use, including methadone or buprenorphine, during pregnancy.

FINDINGS

Among 13 320 pregnancies, 306 (2.3%) were complicated by an overdose, 1753 (13.2%) resulted in a preterm birth and 6787 (50.9%) continued MOUD postpartum. Among infants, 874 (7.6%) were low birth weight at term and 7706 (57.9%) were diagnosed with NAS. As the duration of MOUD use increased, we found a statistically significant decrease in the rate of overdose and preterm birth, a statistically significant increase in the rate of postpartum MOUD continuation and NAS and a decline in term low birth weight. Specifically, for each additional week of MOUD, the adjusted odds of overdose decreased by 2% [adjusted odds ratio (aOR) = 0.98; 95% confidence interval (CI) = 0.97, 0.99], preterm birth decreased by 1% (aOR = 0.99; 95% CI = 0.99, 1.00), postpartum MOUD continuation increased by 95% (aOR = 1.95; 95% CI = 1.87, 2.04) and NAS increased by 41% (aOR = 1.41; 95% CI = 1.35, 1.47). The odds of term low birth weight did not change (aOR = 1.00; 95% CI = 0.99, 1.00), although the rate declined with a longer duration of MOUD use during pregnancy.

CONCLUSIONS

Longer duration of medication for opioid use disorder use during pregnancy appears to be associated with improved maternal and perinatal outcomes.