726 - Earlier Initiation of Medication for Opioid Use Disorder is Associated with Less Non-Opioid Illicit Substance Exposure at Delivery

Medications for Opioid Use Disorder (MOUD) is the standard of care for opioid use disorder during pregnancy and is associated with improved perinatal outcomes. The effect of the timing of MOUD initiation on perinatal outcomes is an area of limited knowledge.

Objective:

To assess the association between MOUD initiation timing with perinatal outcomes: exposure to non-opioid substances (tobacco, cannabis, and illicit cocaine or methamphetamine) in late pregnancy, breastfeeding at discharge, and discharge to mother’s custody.

Design/Methods:

Our study included a retrospective cohort of 470 mother-infant dyads with delivery dates between Jan 2016 and Dec 2021. We extracted data from the electronic health record at a single children’s hospital and confirmed by chart review. We compared perinatal outcomes (birth weight, head circumference, pre-term status, Apgar score, maternal substance use, breastfeeding, and discharge to mother's custody) for mothers initiating MOUD pre-pregnancy ("pre" n=371) to those initiating during pregnancy ("during" n=99) using chi-squared tests and multiple logistic regressions, controlling for potential confounders.

Results:

There were no differences in newborn characteristics (birth weight, head circumference, preterm status, Apgar score) based on MOUD initiation timing (ps >0.40). There were no differences in tobacco (pre: 84%, during: 81%, p=0.48) or cannabis exposure (pre: 48%, during: 45%, p=0.74), breastfeeding at discharge (pre: 77%, during: 74%, p=0.55), or discharge to mother’s custody (pre: 89%, during: 84%, p=0.24). Twenty-nine percent more infants of mothers who initiated MOUD during pregnancy were exposed to non-opioid illicit substances (cocaine or methamphetamine) in late pregnancy (pre: 25%, during: 54%, p< 0.001). The odds of being exposed to non-opioid illicit substances in utero were 3.4 times greater (95% CI: 1.64, 6.82; p=0.001) for infants with mothers initiating MOUD during pregnancy compared to mothers initiating MOUD pre-pregnancy, controlling for maternal tobacco and cannabis use as confounders.

Conclusion(s): Perinatal exposure to non-opioid illicit substances (cocaine or methamphetamine) was higher among mothers initiating MOUD during pregnancy. These findings underscore the importance of efforts to identify and treat women of childbearing age with opioid use disorder before a pregnancy occurs to reduce potentially harmful perinatal exposures. Both groups in our cohort had relatively high rates of breastfeeding and maternal custody at discharge, underscoring the importance of MOUD treatment in pregnancy in promoting positive family outcomes.