Effect of Bathing for Pain Relief During the First Stage of Labor: A Systematic Review and Meta-Analysis

To evaluate the benefits and harms of bathing during the first stage of labor among healthy women with uncomplicated singleton cephalic pregnancies at ≥ 36 weeks' gestation.

Randomized controlled trials comparing warm-water bathing during the first stage of labor with no bathing were included. MEDLINE (PubMed), Cochrane Database of Systematic Reviews, CENTRAL, and Ichu-shi Web (updated to December 2024) were searched for English- and Japanese-language studies. Two reviewers independently assessed risk of bias using the Cochrane Risk of Bias 1.0 tool, and evidence certainty was appraised with GRADE. Random-effects meta-analyses reported risk ratios (RRs) or mean differences with 95% prediction intervals (PIs), and I² statistics.

Nine studies from eight countries (1994-2018; n = 1823) met inclusion criteria. Bathing did not significantly affect regional analgesia use (RR 0.91, 95% PI 0.82-1.01; I² = 0%), perineal trauma, spontaneous vaginal birth, intact perineum, caesarean section, abnormal fetal heart rate patterns, neonatal infection, or episiotomy. Instrumental vaginal birth was reduced (RR 0.78, 95% PI 0.61-0.98; I² = 0%). Satisfaction tended to be higher in the bathing group, though evidence was limited to two small heterogeneous trials.

Evidence certainty was low to very low because of risk of bias, imprecision, lack of blinding, and limited woman-reported outcomes. Bathing appears safe for mothers and infants and may reduce instrumental delivery, but a clear analgesic-sparing effect was not shown. Implementation should ensure tub hygiene, water temperature regulation, and regular maternal and fetal monitoring.

Register name: Effect of Bathing for Pain Relief During the First Stage of Labor: A protocol for a systematic review and meta-analysis. Registration DOI: https://doi.org/10.17605/OSF.IO/J9GTS.