Menstrual cycle, female hormone use and urinary incontinence in premenopausal women.

Our aim was to study the association between menstrual cycle characteristics, the use of female hormones and urinary incontinence (UI) in an age-stratified random population sample of 2158 premenopausal women who answered a questionnaire on urinary incontinence. Episodes of UI during 1997 were reported by 18.3% and one or more episodes of UI the preceding year by 3.9%. Based on multiple logistic regression, self-reported UI the day before answering the questionnaire was found to be associated with current hormone use for menstrual disorders (OR 2.7, 95% CI 1.2-6.6), a recent decrease in bleeding duration (OR 2.2, 95% CI 1.3-3.7), being on days 11-15 before the expected end of the menstrual cycle the preceding day (OR 2.6, 95% CI 1.3-5.0), and with general UI risk factors, i.e. vaginal childbirth, childhood enuresis, BMI >/=530 and exposure to abdominal and/or gynecologic surgery. The findings are in accordance with a hypothesis of hormonal variation being a risk indicator of UI in premenopausal women.