title: The effect of antenatal pelvic floor muscle training on labor and delivery outcomes: a systematic review with meta-analysis.
abstract: OBJECTIVE
  Pelvic floor muscle training (PFMT) has been widely used to prevent and treat urinary incontinence; however, the possible effect of antenatal PFMT on labor and delivery is still not clear. The purpose of the study was to investigate the possible effect of antenatal PFMT on labor and delivery.
  
  
  METHODS
  A systematic review of the scientific literature was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. Randomized or quasi-randomized controlled studies of an obstetric population who had done antenatal PFMT met the inclusion criteria. Data about labor and delivery outcomes included the first stage of labor, the second stage of labor, episiotomy, instrumental delivery, and perineal laceration. The nine English and four Chinese databases were searched from their inception through November 6, 2014. Fixed or random effects models were selected based on study heterogeneity. The weighted mean differences (WMDs) and odds ratios (ORs) with the corresponding 95 % confidence intervals (CIs) were calculated to assess the association between PFMT and the labor and delivery outcomes.
  
  
  RESULTS
  Twelve studies were identified, involving a total of 2,243 women, in which 1,108 were PFMT and 1,135 controls. They indicated that PFMT during pregnancy significantly shortened the first and second stage of labor in the primigravida (WMD = -28.33, 95 % CI: -42.43 to -14.23, I(2) = 0.0 % , and WMD = -10.41, 95 % CI: -18.38 to -2.44, I(2) = 64.0 % respectively). In the subgroup analysis on the second stage of labor, heterogeneity decreased for subgroups of China and European countries (I(2) = 0.0 %, P = 0.768 and I(2) = 0.0 %, P = 0.750 respectively), but statistically significant association only existed in the subgroup of China (WMD = -17.42, 95 % CI: -23.41 to -11.43). When evaluating the effect on the rates of episiotomy, instrumental delivery and perineal laceration, the meta-analysis showed that the results were not significant (OR = 0.75, 95 % CI: 0.54 to 1.02; OR = 0.84, 95 % CI: 0.61 to 1.17 and OR = 0.96, 95 % CI: 0.66 to 1.40 respectively).
  
  
  CONCLUSIONS
  Antenatal PFMT might be effective at shortening the first and second stage of labor in the primigravida. The moderate heterogeneity for the second stage of labor data need further study. Antenatal PFMT may not increase the risk of episiotomy, instrumental delivery, and perineal laceration in the primigravida.
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health, Shandong University, 44 Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China.
authors.forename: Yihui
authors.initials: Y
authors.lastname: Du
authors.affiliation: Department of Women Health Care, Jinan Maternal and Child Care Hospital, Jinan, Shandong, People's Republic of China, 250001.
authors.forename: Li
authors.initials: L
authors.lastname: Xu
authors.affiliation: Center for Health Management and Policy, Key Lab of Health Economic and Policy Research of Ministry of Health, Shandong University, Jinan, Shandong, People's Republic of China.
authors.forename: Lilu
authors.initials: L
authors.lastname: Ding
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health, Shandong University, 44 Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China.
authors.forename: Yiping
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Epidemiology and Health Statistics, School of Public Health, Shandong University, 44 Wenhua Xi Road, Jinan, 250012, Shandong, People's Republic of China. zhipingw@sdu.edu.cn.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Wang
mesh_terms: D036861:Delivery, Obstetric / Q000009:adverse effects*; D026241:Exercise Movement Techniques; D005260:Female; D006801:Humans; D007747:Labor Stage, First; D007748:Labor Stage, Second; D017773:Pelvic Floor / Q000502:physiology*; D011247:Pregnancy; D016032:Randomized Controlled Trials as Topic
keywords: Delivery; Labor; Meta-analysis; Pelvic floor muscle; Training