Electrophysical resources for the treatment of acute perineal pain after vaginal delivery: A systematic review with meta-analysis.

This systematic review aimed at synthesizing evidence regarding the effectiveness of electrophysical resources for perineal acute pain relief after vaginal delivery in the early post-partum period. It included randomized controlled trials comparing electrophysical resources with reference groups for acute pain relief on primiparous women. Search strategy was conducted in PubMed, Embase, Lilacs, Scopus, Cochrane and Web of Science. Meta-analysis was conducted to synthesize the results. The risk of bias was assessed using PEDro scale and certainty of evidence was assessed using the GRADE approach. Seventeen studies with 1970 postpartum women were included. The evidence synthesis demonstrated high confidence in the positive effects of cryotherapy for perineal pain relief up to 4 h after its application, compared to routine care (mean difference -1.57, 95% CI: -2.18 to -0.96). Low-level laser therapy (LLLT) was found to be ineffective when compared to a placebo, with evidence showing moderate confidence (0.03, 95% CI: -0.69-0.76). The evidence for Transcutaneous Electrical Nerve Stimulation (TENS) was less conclusive: very low confidence was found regarding its positive effects compared to a placebo (MD -2.63, 95% CI: -4.85 to -0.41). Moderate confidence was found regarding TENS compared to routine care (MD -1.49, 95% CI: -1.90 to -1.09). In conclusion, high-certainty evidence on the effectiveness of cryotherapy applied after 1-4 h postpartum and moderate-certainty evidence on the effectiveness of TENS when combined with routine care. Moderate-certainty evidence indicates a lack of evidence on LLLT for perineal pain control. PERSPECTIVE: Cryotherapy can be recommended for perineal pain relief based on high and moderate confidence evidence. Applications should be performed considering patient preferences. Perineal application of LLLT, TENS and US require further studies with stronger protocol and methodological design to provide more consistent conclusions about their clinical use in postpartum period.