Understanding the indications and consequences of analgesia options on labor outcomes is essential for effective patient counseling and informed decision-making during childbirth. In recent years, the use of nitrous oxide for labor analgesia has increased in the United States; however, its impact on key maternal and neonatal outcomes remains incompletely understood. These outcomes include mode of delivery, labor duration, patient satisfaction, neonatal Apgar scores, neonatal intensive care unit (NICU) admissions, and rates of conversion to alternative analgesia. The objective of this study was to conduct a comprehensive literature review evaluating the association between nitrous oxide use and labor outcomes while identifying gaps in the current evidence. A systematic PubMed search was performed for articles published within the past 10 years using the terms nitrous oxide, labor outcomes, and labor analgesia. Studies of laboring patients receiving nitrous oxide that reported maternal or neonatal outcomes were included. Articles lacking relevant outcomes or not involving labor analgesia were excluded. Of over 100 articles identified, 36 met inclusion criteria. Data were extracted and qualitatively synthesized due to heterogeneity in study design and outcome measures. Overall, nitrous oxide provides modest analgesia with relatively high patient satisfaction; however, its effects on labor outcomes remain inconclusive. Multiparous patients may have a lower likelihood of conversion to epidural analgesia, while no difference is observed in nulliparous patients. Cesarean delivery rates do not appear to differ with nitrous oxide use. Compared with opioids, nitrous oxide demonstrates similar analgesic efficacy with fewer side effects and no significant differences in labor outcomes. Evidence regarding labor duration is conflicting, and neonatal outcomes are comparable across analgesic modalities. Although nitrous oxide appears safe, current evidence is limited by small sample sizes and heterogeneous methodologies. Further large-scale, prospective studies are needed to better define its impact on maternal and neonatal outcomes.
