Nitrous oxide in labor and neonatal hyperbilirubinemia: a retrospective propensity score–matched study (2012–2023)
Authors' conclusion
Intrapartum nitrous oxide analgesia was not associated with increased neonatal hyperbilirubinemia compared with other labor analgesic modalities. However, the NICU admission rate after nitrous oxide exposure was significantly higher.
Study context
- Population
- Singleton pregnancies at ≥35 weeks' gestation, Slovenian National Perinatal Database, 2012–2023
- Participants
- 32,744 births
- Exposure
- Pethidine vs Nitrous oxide
- Nitrous oxiden = 8,186reference
- Remifentaniln = 8,186
- Pethidinen = 8,186
- Neuraxial analgesian = 8,186
- Outcome
- Neonatal hyperbilirubinemia
Methodological detailspopulation-based, propensity score-matched, 1:1:1:1 matching
- Population-based
- Propensity score-matched
- 1:1:1:1 matching
Main finding
As reported in the abstract
P = 0.0002
- Difference across all exposures
- P = 0.0003
Observational data: associations, not effects.
Secondary outcomes
- Neonatal intensive care unit (NICU) admission — Nitrous oxide
- 244 events
- Apgar <7 at 1 min — Pethidine
- 245 events
- Neonatal hypoglycemia — Remifentanil
- 222 events
- NICU admission — More common after nitrous oxide exposure
- P < 0.001
- Apgar <7 at 1 min — More frequent after pethidine exposure
- P < 0.001
- Neonatal hypoglycemia — More frequent with remifentanil
- P < 0.001
Apgar <7 at 5 min and respiratory morbidity (composite)
- No significant differences between exposures
Original publication
Nitrous oxide in labor and neonatal hyperbilirubinemia: a retrospective propensity score–matched study (2012–2023). Int J Obstet Anesth. Published 13 December 2025. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →