Overactive bladder syndrome is associated with detrusor overactivity and abnormal voiding pattern in nulliparous women

Background Pregnancy and childbirth are frequently associated with overactive bladder syndrome (OAB). However, the role of parous effects in OAB among nulliparous (NP) women remains controversial. Methods This study investigated abnormal voiding patterns and detrusor overactivity (DO) among NP women with OAB in comparison with parous women. From August 2011 to December 2018, 906 patients met the inclusion criteria for participation and were divided into three groups: 221 patients in the NP group, 571 patients in the normal spontaneous delivery (NSD) group, and 114 patients in the cesarean section (CS) group. Urodynamic study examinations were performed, and the presence of DO, abnormal voiding patterns, and maximum urethral closure pressure (MUCP) was recorded. Data were analyzed using analysis of variance, χ2 tests, and independent t tests. Results Compared with parous women in the NSD and CS groups, patients in the NP group had a significantly higher prevalence of abnormal voiding patterns, DO, and MUCP. Furthermore, abnormal voiding patterns were significantly associated with DO and MUCP, respectively, especially in the NP group. Conclusion We hypothesized that hypertonicity or poor relaxation of the pelvic muscle in NP women may cause functional BOO, which is related to their OAB.