Association between intrapartum fetal pulse oximetry and adverse perinatal and long-term outcomes: A systematic review and meta-analysis

Background: Fetal pulse oximetry may improve intrapartum fetal evaluation by providing a non-invasive measurement of fetal oxygen saturation (FSpo₂). Objectives: To assess the association between abnormal intrapartum FSpo₂ and perinatal and long-term neurodevelopmental outcomes, and to evaluate if the addition of the measurement of FSpo₂ to established forms of fetal monitoring, such as fetal heart rate monitoring, affects birth, perinatal, and long-term neurodevelopmental outcomes. Search Strategy: We conducted a comprehensive search of PubMed, EMBASE, CINAHL, The Cochrane Library, Web of Science, ClinicalTrials.gov, and WHO ICTRP from database inception through February 2024, with no restrictions on date, geographic region, country income level, or language. Selection Criteria: Studies involving women in labor with a cephalic baby were included. Two interventions were reviewed: (1) low FSpo₂ (<30%), and (2) the use of fetal pulse oximetry during labor. Data Collection and Analysis: Independent reviewers screened studies, extracted data, and assessed quality using the Risk of Bias tool and the Newcastle-Ottawa Scale. The approach evaluated evidence certainty. A random-effects meta-analysis followed PRISMA and MOOSE guidelines. Main Results: Forty-seven studies with 13 071 mother-infant pairs were included. FSpo₂ <30% was associated with umbilical artery pH <7.15 (odds ratio [OR] 7.86, 95% confidence interval [CI] 3.29–18.75, I² = 71%, P < 0.001), 5-min Apgar score less than 7 (OR 16.63, 95% CI 5.64–49.01, I² = 30%, P < 0.001) and NICU admission (OR 5.89, 95% CI 1.73–20.01, I² = 0%, P < 0.005). FSpo₂ monitoring combined with fetal heart rate monitoring was associated with lower odds of cesarean section for non-reassuring fetal status (OR 0.59, 95% CI 0.40–0.86, I² = 71%, P = 0.006) without impacting 5-min Apgar scores <7 (OR 0.66, 95% CI 0.37–1.17, I² = 0%, P = 0.160) or neonatal intensive care unit admissions (OR 0.98, 95% CI 0.82–1.18, I² = 0%, P = 0.840). Conclusion: FSpo₂ monitoring combined with fetal heart rate monitoring may reduce unnecessary cesarean sections for suspected fetal distress without affecting short-term neonatal outcomes. The association between FSpo₂ <30% and adverse perinatal outcomes supports its potential as a valuable adjunct in intrapartum monitoring.