Oral contraceptive use and incident urinary incontinence in premenopausal women

Recent data in postmenopausal women indicate that current and past use of exogenous hormones is related to urinary incontinence risk. Little is known about exogenous hormones and risk of urinary incontinence in younger women. We investigated the association between oral contraceptive pills and incident urinary incontinence in premenopausal women enrolled in the Nurses' Health Study II.

Participants reported use of oral contraceptive pills from 1989 to 2001. Among 21,864 premenopausal women 37 to 54 years old reporting no urinary incontinence in 2001 we identified 749 with incident urinary incontinence at least weekly between 2001 and 2003. Odds ratios and 95% confidence intervals were estimated using multivariable logistic regression.

Women who had ever used oral contraceptive pills had a statistically significant 27% (95% CI 1-59) increased odds of experiencing urinary incontinence at least weekly compared with those who never used oral contraceptive pills. In women with 10 or more years of use the odds ratio increased to 1.48 (95% CI 1.13-1.95). Ever using oral contraceptive pills was specifically associated with urgency urinary incontinence (OR 2.48, 95% CI 1.07-5.76) rather than stress urinary incontinence (OR 1.04, 95% CI 0.78-1.40). Although we had limited information on urinary tract infection, control for urinary tract infection did not alter these findings.

Use of oral contraceptive pills may be associated with a modest increase in the odds of urinary incontinence among premenopausal women. However, this is one of the first reports of such an association and, thus, further research is needed to confirm our findings and investigate possible mechanisms.