Does childbirth play a role in the etiology of rectocele?

Introduction and hypothesis: Rectoceles are common among parous women and they are believed to be due to disruption or distension of the rectovaginal septum as a result of childbirth. However, the etiology of rectocele is likely to be more complex since posterior compartment prolapse does occur in nulliparous women. This study was designed to determine the role of childbearing as an etiological factor in true radiological rectocele. Methods: This was a secondary analysis of the data from 657 primiparous women recruited as part of a previously reported study and another ongoing prospective study. Women were invited for antenatal and postnatal appointments comprising an interview, clinical examination and translabial ultrasonography. The presence and depth of any rectocele were determined on maximum Valsalva maneuver, as was descent of the rectal ampulla. Potential demographic and obstetric factors as predictors of rectocele development were evaluated using either multiple regression or logistic regression analysis as appropriate. Results: A true rectocele was identified in 4 % of women antenatally and in 16 % after childbirth (P < 0.001). Mean rectocele depth was 13.5 mm (10 – 23.2 mm). The mean antepartum position of the rectal ampulla on Valsalva maneuver was 4.39 mm above and it was 1.64 mm below the symphysis pubis postpartum (P < 0.0001). De novo appearance of true rectocele was significantly associated with a history of previous <20 weeks pregnancy and fetal birth weight. Body mass index and length of the second stage were associated with rectocele depth increase. Conclusions: Childbirth seems to play a distinct role in the pathogenesis of rectocele. Both maternal and fetal factors seem to contribute.