Prevalence and Predictors of Urinary Incontinence at 1 Year Postpartum.

OBJECTIVES

Postpartum urinary incontinence estimates range from 13% to 47%. Clinical factors associated with incontinence 1 year after first delivery are varied. We assessed the prevalence of and factors associated with urinary incontinence in primiparous women at 12 months postpartum.

METHODS

Ancillary analysis of 99 nulliparous women from a prospective cohort study that assessed participants during the first and third trimesters and 12 months postpartum. Our primary outcome was urinary incontinence 12 months postpartum. Women were asked "How often do you experience urine leakage?" and considered to have urinary incontinence if a response other than "never" was reported. We collected vaginal swabs for assessment of matrix metalloproteinase-9 activity, a measure of tissue remodeling. Bivariable and logistic regression analyses were used to compare women with and without postpartum urinary incontinence.

RESULTS

Of 99 primiparous women, 55% (n = 54) reported urinary incontinence at 12 months postpartum. Logistic regression demonstrated that urinary incontinence during pregnancy (odds ratio, 34.3; 95% confidence interval, 7.9-149.2) and a decrease in matrix metalloproteinase 9 activity between the first and third trimesters (odds ratio, 19.34; 95% confidence interval, 3.47-107.84) were associated with postpartum urinary incontinence. The sensitivity and specificity of urinary incontinence during pregnancy for predicting postpartum urinary incontinence were 87% and 67%, respectively. The positive and negative predictive values were 76% and 81%, respectively.

CONCLUSIONS

Urinary incontinence affected 55% of primiparous women at 12 months postpartum. Urinary incontinence during pregnancy was strongly associated with postpartum incontinence. Importantly, vaginal tissue protease activity during pregnancy represents a possible mechanism for and biomarker of postpartum urinary incontinence.