Impact of parity and delivery mode on pelvic floor function in young women: a 3D ultrasound evaluation

Introduction and hypothesisThe objectives were to evaluate clinical and anatomical parameters assessed by three-dimensional pelvic floor ultrasound (3D ultrasound) in parous and nulliparous women of childbearing age and to assess underreported symptoms of sexual dysfunction (SD), urinary incontinence (UI) and flatus incontinence (FI).MethodsWomen without complaints of pelvic floor dysfunction, aged 20-50 years, were eligible for this prospective cross-sectional study. They completed the King's Health Questionnaire, Female Sexual Function Index and St Mark's Incontinence Score adapted for this study. Next, a physical examination and 3D ultrasound were performed. The scores obtained in the questionnaires were compared with the 3D ultrasound data.ResultsIn total, 326 women were invited to participate. Of these, 203 women met the inclusion criteria, and their cases were classified as nulliparity (NU, 59), vaginal delivery (VD, 80), forceps delivery (FD, 18) and caesarean section (CS, 48). These groups were homogeneous regarding age (p=0.096), parity (p=0.051) and body mass index (p=0.06). The hiatal dimension (HD; p=0.003) and transverse diameter (TD) (p=0.001) were significantly different among the groups. Compared with the NU and CS groups, the VD and FD groups had an increased HD and TD. The frequencies of underreported symptoms identified by questionnaires were as follows: SD (46.3%), UI (35%) and FI (28%). After VD and FD, women were more likely to present UI (p<0.001), FI (p<0.001) and SD (p=0.002) than the women with NU and those who had undergone a CS. UI was related to a greater HD (p=0.002) and anteroposterior diameter (p=0.022), FI was associated with a thinner left pubovisceral muscle (p=0.013), and SD was related to a greater HD (p=0.026).ConclusionsThree-dimensional ultrasound can identify mild morphological changes in young women with apparently normal physical examinations, mainly after VD and FD. In such individuals, these findings are associated with higher incidences of underreported sexual, urinary and anal symptoms.