Duration and Timing of In Utero Opioid Exposure and Incidence of Neonatal Withdrawal Syndrome

Distinct Trajectories of Prescription Opioid Exposure in Pregnancy and Risk of Adverse Birth Outcomes

OBJECTIVES

The aim of this study was to identify distinct trajectories of prescription opioid exposure in pregnancy-encompassing both medication for opioid use disorder (MOUD) and opioid analgesics-and explore their associations with birth outcomes.

METHODS

Trajectories were identified using latent class analysis among Wisconsin Medicaid-insured live births 2011-2019. Logistic regression estimated associations between these trajectories and neonatal opioid withdrawal syndrome (NOWS), small for gestational age, preterm birth, birth weight, and gestational age.

RESULTS

Of 138,123 births, 27,293 (19.8%) had prenatal opioid exposure. Five trajectory classes were identified: (1) stable MOUD treatment (5.8%), (2) inconsistent MOUD treatment (3.9%), (3) chronic analgesic use (4.2%), (4) intermittent analgesic use (7.8%), and (5) low-level use of MOUD and analgesics (78.3%). NOWS incidence per 1000 infants was 667 for class 1 (adjusted odds ratio [aOR]: 21.74, 95% confidence interval [CI]: 17.89, 26.41), 570 for class 2 (aOR: 15.35, 95% CI: 12.49, 18.87), 235 for class 3 (aOR: 19.42, 95% CI: 15.93, 23.68), 67 for class 4 (aOR: 6.23, 95% CI: 4.99, 7.76), and 12 for class 5 (aOR: 1.73, 95% CI: 1.47, 2.02). Classes 1-4 had elevated risk of small for gestational age, preterm birth, lower birth weight, and shorter gestational age, with no significant differences among these classes. Among individuals with opioid use disorder, stable MOUD treatment was associated with higher birth weights and longer gestational ages compared to inconsistent treatment, despite higher odds of NOWS.

CONCLUSIONS

Early initiation and consistent MOUD treatment may improve birth weight and gestational age. For pregnant individuals with opioid use disorder using chronic analgesics, transition to MOUD may promote birth outcomes.

Trends in prenatal prescription opioid use among Medicaid beneficiaries in Wisconsin, 2010-2019

OBJECTIVE

To examine changes in prenatal opioid prescription exposure following new guidelines and policies.

STUDY DESIGN

Cohort study of all (262,284) Wisconsin Medicaid-insured live births 2010-2019. Prenatal exposures were classified as analgesic, short term, and chronic (90+ days), and medications used to treat opioid use disorder (MOUD). We describe overall and stratified temporal trends and used linear probability models with interaction terms to test their significance.

RESULT

We found 42,437 (16.2%) infants with prenatal exposure; most (90.5%) reflected analgesic opioids. From 2010 to 2019, overall exposure declined 12.8 percentage points (95% CI = 12.1-13.1). Reductions were observed across maternal demographic groups and in both rural and urban settings, though the extent varied. There was a small reduction in chronic analgesic exposure and a concurrent increase in MOUD.

CONCLUSION

Broad and sustained declines in prenatal prescription opioid exposure occurred over the decade, with little change in the percentage of infants chronically exposed.