Continuous Versus Intermittent Fetal Oxygen Saturation Monitoring Under Regional Anesthesia

Abstract

Background:
Continuous fetal oxygen-saturation monitoring promises earlier recognition of intrapartum hypoxia during neuraxial analgesia; however, reported effects on operative birth vary and no synthesis has focused on regional practice gaps.
Methods:
A protocol was registered with PROSPERO. PubMed was searched from inception to 30 June 2024 combining MeSH and free-text terms for pulse oximetry, fetal monitoring, regional anaesthesia and labour. Randomised or cohort comparisons of continuous versus intermittent saturation monitoring were eligible. Two reviewers performed duplicate screening, data extraction and risk-of-bias appraisal (RoB 2 or Newcastle–Ottawa). Owing to methodological heterogeneity, results were synthesised narratively.
Results:
Thirteen studies met criteria, eight randomised trials and five prospective cohorts, together enrolling 9 274 parturients, of whom 5,316 received continuous monitoring. Four trials showed significant reductions in operative birth for non-reassuring fetal status (relative risk 0.31–0.77), whereas the two largest pragmatic trials were neutral. A saturation below 30 percent sustained for 10 minutes predicted umbilical arterial pH ≤ 7.15 with pooled sensitivity 92.9% and specificity 85 percent. No study reported excess infection; patient acceptability reached 92%; and one economic evaluation estimated savings of AUD 813 per operative birth averted.
Conclusions:
Continuous fetal pulse oximetry under regional anaesthesia accurately identifies prolonged hypoxia and can reduce intervention when paired with clear management thresholds; nonetheless, benefit is inconsistent and further context-specific trials, particularly in the Gulf region, are warranted.