Manual perineal support at the time of childbirth: a systematic review and meta-analysis

BACKGROUND: Genital tract trauma is common with vaginal births and is associated with significant morbidity, particularly with obstetric anal sphincter injuries (OASIS). Debate continues regarding the effectiveness of perineal support during childbirth in reducing the risk of trauma.

OBJECTIVES: This review aimed to assess the effect of routine 'hands on'/manual perineal support (MPS) during childbirth, versus ad hoc/no perineal support ('hands off/poised'), on the risk and degree of perineal trauma.

SEARCH STRATEGY: This review is registered on PROSPERO (http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42014007058). We searched the CENTRAL, Embase, Medline, CINAHL, and OVIDs midwifery and infant care databases (from inception to December 2014).

SELECTION CRITERIA: Published randomised controlled trials (RCTs) and non-randomised studies (NRSs) evaluating any 'hands on' perineal support technique during childbirth.

DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trials for inclusion, data extraction, and methodological quality. Discrepancies were resolved by discussion with a third reviewer.

MAIN RESULTS: We included five RCTs and seven NRSs in the review. Meta-analysis of RCTs did not demonstrate a statistically significant protective effect of MPS on the risk of OASIS (three studies, 6647 women; relative risk, RR 1.03; 95% confidence interval, 95% CI 0.32-3.36; statistical test for heterogeneity I(2) = 71%). Meta-analysis of NRSs showed a significant reduction in the risk of OASIS with MPS (three studies, 74,744 women; RR 0.45; 95% CI 0.40-0.50; I(2) = 32%).

CONCLUSION: Current evidence is insufficient to drive change in practice. An adequately powered randomised trial with an efficient design to evaluate the complex interventions adopted as part of MPS policies, ensuring controlled childbirth, is urgently needed.