Risk Factors and Nomogram for Postpartum Myofascial Pelvic Pain: A Prospective Cohort Study.

Background: Myofascial pelvic pain (MFPP) is a common but underrecognized postpartum complication. Early identification of women at increased risk may facilitate targeted surveillance and timely postpartum rehabilitation. This study aimed to identify risk factors for postpartum MFPP and develop a predictive nomogram. Methods: This prospective cohort study included 671 women who delivered at a tertiary hospital between December 2022 and December 2024. Postpartum MFPP was diagnosed using standardized trigger point assessments by two independent blinded specialists. Participants were randomly assigned to training (n = 505) and validation (n = 166) sets. Multivariable logistic regression was used to identify independent risk factors and construct a nomogram. Results: The incidence of MFPP was 12.9% in the training set and 11.4% in the validation set. Four independent risk factors were identified: neonatal birth weight ≥4 kg (OR 3.632), vaginal laceration (OR 2.448), parity ≥3 (OR 2.975), and history of dyspareunia (OR 2.381). The nomogram achieved an AUC of 0.681 in the training set and 0.656 in the validation set, indicating moderate discriminative ability. Calibration analysis showed acceptable agreement between predicted and observed risks, and decision curve analysis suggested a positive net clinical benefit across clinically relevant threshold probabilities. Conclusion: Macrosomia, vaginal laceration, grand multiparity, and history of dyspareunia are independently associated with postpartum MFPP. The proposed nomogram may serve as a preliminary and clinically accessible tool for early risk stratification, although further multicenter validation is needed before widespread clinical application.