Title : Visualization of pelvic floor structural changes beginning in pregnancy: Bladder descent angle as a novel indicator for lifelong women’s health
Abstract:
Background: Urinary Incontinence (UI) is a major symptom of pelvic floor dysfunction in women and commonly develops during pregnancy and childbirth. Approximately 40% of women experience UI in the early postpartum period, and symptoms may persist long term, making UI a significant concern for women’s lifelong health. However, the structural changes in pelvic floor support from pregnancy through the postpartum period and their relationship with UI remain unclear. We previously developed a quantitative method to assess bladder descent using Transperineal Ultrasound (TPUS), termed the Bladder Descent Angle (BDA), and demonstrated its validity and reproducibility. This method enables noninvasive visualization of pelvic floor structural changes beginning in pregnancy and may contribute to improving lifelong pelvic floor health.
Objective: To longitudinally evaluate changes in the BDA from late pregnancy to one month postpartum and examine associations with UI symptoms and maternal factors, and to assess its potential as an early structural indicator of pelvic floor health.
Methods: This prospective longitudinal study included 100 women with singleton pregnancies. BDA was measured using TPUS in late pregnancy and at one month postpartum. UI symptoms were assessed using the International Consultation on Incontinence Questionnaire–Short Form (ICIQ-SF). Associations between BDA, UI symptoms, and clinical background factors were analyzed statistically.
Results: BDA was significantly associated with UI symptoms both in late pregnancy and at one month postpartum, with larger BDA values corresponding to more severe UI symptoms. Late-pregnancy BDA alone showed limited ability to predict postpartum UI; however, predictive performance improved when maternal age and late-pregnancy symptom severity were included. Changes in BDA (ΔBDA) were not independently associated with postpartum UI, although higher maternal age tended to relate to reduced recovery of pelvic floor support.
Conclusion: Structural changes in the pelvic floor begin during pregnancy and are closely associated with early postpartum UI. BDA measured by TPUS may serve as a novel, noninvasive indicator of pelvic floor vulnerability. Early evaluation during pregnancy may facilitate preventive interventions and help maintain pelvic floor health across the lifespan.
