A Prediction Model for Pelvic Floor Recovery After Vaginal Birth With Risk Factors

Abstract

Importance Although parturients report few postpartum symptoms, birth is clearly associated with future symptom development. The ability to identify asymptomatic at-risk women would facilitate prevention. Objective The aim of the study was to develop a model predicting abnormal recovery in women at risk for childbirth-associated pelvic floor injury. Study Design Women undergoing first vaginal birth at high risk of pelvic floor injury underwent examinations and ultrasound imaging and completed 6-week and 6-month postpartum questionnaires. We defined “abnormal” recovery as having ≥1 of the following 3 findings: (1) levator ani injury, (2) decreased objective pelvic floor strength, and (3) Pelvic Organ Prolapse Quantification point Bp ≥0. Descriptive statistics and bivariate analyses compared “normal” and “abnormal” recovery. Birth characteristics, 6-week examinations, and questionnaires potentially predicted abnormal recovery at 6 months. Significant variables were included as candidates in the multivariable logistic regression predicting “abnormal” recovery after birth. Results Fifty-four women (63.5%) had normal and 31 (36.5%) had abnormal recovery at 6 months. At 6 weeks, women with abnormal recovery had decreased pelvic floor strength by Oxford scores (3 [2–5], 6 [2–8]; P = 0.002), lower point Bp (−1 [−3 to 0], −2 [−3 to −1]; P = 0.02), larger genital hiatus (4 [3 to 4], 3 [3 to 3.5]; P = 0.02), and higher levator ani injury rate (76.7%, 22.4%; P < 0.001). Between-group questionnaire differences were not clinically significant. Our final model included postpartum examination findings or birth characteristics: Oxford Scale, 6-week Pelvic Organ Prolapse Quantification GH strain, infant head circumference, and second stage ≥120 minutes. The area under the curve for predicting abnormal recovery at 6 months was 0.84, indicating a good sensitivity and specificity balance. Conclusion The model identifies women at risk for an abnormal recovery trajectory.