Urinary incontinence in nulliparous women before and during pregnancy: Prevalence, incidence, and associated risk factors

Introduction: Few studies have examined associations of prepregnancy urinary incontinence (UI). Methods: Multicentre prospective pregnancy cohort study (n=1,507) using standardised measures to assess frequency and severity of UI. Results: Prevalence of UI increased from 10.8% in the 12 months before the index pregnancy to 55.9% in the third trimester. Stress incontinence (36.9%) and mixed incontinence (13.1%) were more common during pregnancy than urge incontinence alone (5.9%). UI before pregnancy was associated with childhood enuresis (adjusted odds ratio (AdjOR)=2.4, 95% confidence interval (CI) 1.6-3.4), higher maternal body mass index (AdjOR=2.3, 95% CI 1.4-3.8), and previous miscarriages or terminations (AdjOR=1.6, 95% CI 1.1-2.3). The strongest predictor of incident UI in pregnancy was occasional leakage (less than once a month) before pregnancy (AdjOR=3.6, 95% CI 2.8-4.7). Conclusions: Further research is needed to elucidate the complex interplay of prepregnancy and pregnancy-related factors in the aetiology of UI in nulliparous women.