Association Between Childbirth and Overactive Bladder Symptoms: A Nationwide Internet-Based Study of 4800 Japanese Women.

INTRODUCTION

Overactive bladder (OAB) is a prevalent condition, particularly among women, and is associated with substantial economic and quality-of-life burdens. Although stress urinary incontinence during and after pregnancy is well documented, the association between childbirth and OAB symptoms remains unclear. This study aimed to investigate the relationship between childbirth history and OAB symptoms among Japanese women using a large-scale internet-based survey.

METHODS

A total of 4800 Japanese women aged 40 years and older were recruited through an online survey platform. Participants were stratified by age and completed the Overactive Bladder Symptom Score (OABSS) questionnaire. Subjects were grouped based on childbirth history (parous vs. nulliparous), and OABSS scores were compared between the groups. Subgroup analyses were conducted for women aged 40-60 years and for parous women based on delivery mode (vaginal vs. cesarean).

RESULTS

The OABSS total score and scores for nocturia, urgency, and urgency incontinence were significantly higher in the parous group compared to the nulliparous group (all p < 0.001). These trends persisted in the 40-60-year-old subgroup. No significant differences in OABSS scores were found between women who had vaginal deliveries and those who had cesarean sections. BMI showed minimal correlation with OABSS, while symptom severity increased with age.

CONCLUSION

A history of childbirth may be associated with more severe OAB symptoms among Japanese women, independent of age. These findings highlight childbirth as a potential risk factor for OAB and underscore the need for long-term urinary health monitoring in women.