Labor Analgesia. A Systematic Review and Meta-Analysis of Non-Pharmacological Complementary and Alternative Approaches to Pain during First Stage of Labor

The aim of the study was to conduct a meta-analysis to evaluate the efficacy of non-invasive and nonpharmacological techniques on labor first-stage pain intensity. Literature databases were searched from inception to May 2021, and research was expanded through the screening of previous systematic reviews. Inclusion criteria were: (1) population: women in first stage of labor; (2) intervention: non-pharmacological, non-invasive, or minimally invasive intrapartum analgesic techniques alternative and/or complementary to pharmacological analgesia; (3) comparison: routine intrapartum care or placebos; (4) outcomes: subjective pain intensity; and (5) study design: randomized controlled trial. Risk of bias of included studies was investigated, data analysis was performed using R version 3.5.1. Effect size was calculated as difference between the control and experimental groups at posttreatment in terms of mean pain score. A total of 63 studies were included, for a total of 6146 patients (3468 in the experimental groups and 2678 in the control groups). Techniques included were massage (n = 11), birth balls (n = 5) mind-body interventions (n = 8), heat application (n = 12), music therapy (n = 9), dance therapy (n = 2), acupressure (n = 16), and transcutaneous electrical nerve stimulation (TENS) (n = 8). The present review found significant evidence in support of the use of complementary and alternative medicine for labor analgesia, and different methods showed different impact. However, more high-quality trials are needed.