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CME Credit Offered
CME Credit Offered
Abstract Award
Abstract Award
Recording available 2/16-5/2
Recording available 2/16-5/2
AIUM Credit
AIUM Credit
Foundation Awardee
Foundation Awardee
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Abstract Award
Abstract Award
Foundation Awardee
Foundation Awardee

Poster Session 2

Category: Physiology/Endocrinology

Poster Session 2

(467) Cord Tissue Analysis of Prenatal Buprenorphine Exposure and Neonatal Withdrawal

Wednesday, February 11, 2026
3:30 PM - 5:00 PM  
Foundation Awardee
Objective:
Neonatal opioid withdrawal syndrome (NOWS) occurs less frequently in buprenorphine than methadone-exposed pregnancies. However, maternal buprenorphine dose does not reliably predict NOWS severity. This study assessed whether umbilical cord buprenorphine and norbuprenorphine levels are associated with maternal dose and NOWS severity.

Study Design:
Secondary analysis of a multi-site prospective study of pregnancies with opioid use disorder (OUD) between 2021-2025. Patients included if maintained on buprenorphine, delivered ³34 weeks and had biospecimen collected at delivery. Major fetal anomalies and missing data were exclusions.  Maternal and neonatal characteristics were abstracted. Umbilical cord tissue was collected after delivery, drained of blood, stored at -80°C and underwent mass spectrometry for quantification of buprenorphine and norbuprenorphine levels. NOWS was defined as any Finnegan score >4; severe NOWS as requiring pharmacotherapy or Finnegan score >24 in 24 hours. Pearson correlations assessed relationships between maternal dose, cord drug levels and NOWS. P< 0.05 was significant.

Results:
Out of 83 patients with OUD, 34 received buprenorphine. Most were non-Hispanic White (91%), multiparous (77%), and had vaginal deliveries (71%). NOWS was diagnosed in 74% (n=25) of neonates, and 27% (n=9) had severe NOWS. Maternal buprenorphine dose moderately correlated with cord buprenorphine levels (r=0.39, p=0.03), but not with cord norbuprenorphine levels (r=0.10, p=0.59). Cord drug levels did not differ between severe and non-severe NOWS cases and were not correlated with Finnegan scores.

Conclusion:
Maternal buprenorphine dose was moderately associated with cord buprenorphine levels but not with norbuprenorphine. Neither cord buprenorphine nor norbuprenorphine levels were linked to NOWS severity. Other factors may influence NOWS beyond umbilical cord drug concentrations.