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Published on: August 28, 2020
Overactive Bladder in Late Pregnancy to 1 Year After First Vaginal Delivery
Whitney K Hendrickson1, Amanda A Allshouse2, Ingrid E Nygaard1
1From the Divisions of Urogynecology.
Importance:
Understanding overactive bladder (OAB) during pregnancy and postpartum may increase our knowledge of pathophysiology.
Objectives:
The purpose of this study was to understand the prevalence and severity of OAB during pregnancy through 1 year postpartum as well as the associated factors.
Study Design:
This is a secondary analysis of a prospective cohort study evaluating primiparous women with a singleton term vaginal delivery assessed at the third trimester, 8 weeks postpartum, and 1 year postpartum. Overactive bladder was defined as urinary urgency plus nocturia or frequency, or urgency urinary incontinence (UUI). Overactive bladder severity was defined using average visual analog scores (0-100) from OAB symptoms on the Epidemiology of Prolapse and Incontinence Questionnaire. We evaluated associations with OAB at each time point using logistic regression.
Results:
Among 579 participants, mean age was 29 years. Overactive bladder prevalence was higher at 8 weeks postpartum (23%) than at the third trimester (18%, P = 0.03) and 1 year postpartum (19%, P = 0.03). Overactive bladder severity was higher at the third trimester (42.2) than at 8 weeks postpartum (23.3, P = 0.008), but not at 1 year postpartum (29.1, P = 0.1). In those with OAB, UUI severity was higher at 1 year postpartum compared with that at the third trimester ( P = 0.02). Younger age was associated with third trimester OAB. At 8 weeks postpartum, OAB was associated with older age, urinary tract infection after delivery, birth weight ≥3,500 g, and third trimester OAB. At 1 year postpartum, OAB was associated with birth weight ≥3,500 g and third trimester OAB.
Conclusions:
Overactive bladder affects 1 in 5 primiparous women during pregnancy or after vaginal delivery. The increased severity of UUI postpartum and the association between higher birth weight and OAB postpartum suggest an effect of delivery.
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