OBJECTIVE:

To estimate the effect of 2 years of treatment with ultralow-dose transdermal estradiol (E2) on incontinence in postmenopausal women.

METHODS:

Ultra Low Dose Transdermal estRogen Assessment (ULTRA) was a multicenter, randomized, double-blinded, placebo-controlled trial of unopposed ultralow-dose (0.014 mg/d) transdermal E2 for prevention of osteoporosis in 417 postmenopausal women aged 60 to 80 years. Frequency of incontinence episodes was assessed at baseline and after 4 months and 2 years of treatment using a self-reported questionnaire. We used an intention-to-treat analysis to compare change in incontinence frequency, improved (decreased 2 or more episodes per week), unchanged (increased or decreased no more than 1 episode per week), or worsened (increased 2 or more episodes per week) between the E2 and placebo groups among women with and without at least weekly incontinence at baseline.

RESULTS:

At baseline, the prevalence of at least weekly incontinence was similar between E2 and placebo groups (43%). After 2 years, there was no difference between groups in the proportions of women with incontinence at baseline whose incontinence improved, worsened, or was unchanged. The odds ratio for worsening incontinence in the E2 compared with placebo group was 1.35 (95% confidence interval 0.75-2.42. In women without incontinence at baseline, the odds of developing at least weekly incontinence after 2 years in the E2 compared with placebo group was not significant (odds ratio 1.2, 95% confidence interval 0.7-2.2).

CONCLUSION:

Two years of treatment with unopposed ultralow-dose transdermal E2 did not substantially change the frequency of incontinence symptoms or alter the risk of developing at least weekly incontinence.

LEVEL OF EVIDENCE:

I.