While vaginal estrogen is often thought of as a treatment for vaginal dryness (and it is) and also for treating painful sexual activity in menopause (also true), there is another benefit that is often forgotten: reducing the risk of urinary tract infections (UTIs). As many women struggle with recurrent UTIs, I think it’s worth discussing the role of estrogen because not everyone is seeing a provider who is up to date on these benefits. Sadly, sometimes, that includes a few OB/GYNs and urologists. Another reason to discuss vaginal estrogen is that while it can be helpful, it’s not 100% preventative, so it’s good for people to know the limitations of a specific therapy so they are not disappointed and stop using it, thinking it’s not helpful. And finally, the more you know, the better!
Recurrent UTIs: Scope of the Issue
For women, the lifetime risk of having a bladder infection is 50%. Recurrent UTIs are defined as two or more infections in 6 months or three or more in 12 months, and the risk of having at least one episode of recurrent infections ranges from 10-18%, depending on the study. What women in menopause need to know is that age is a significant risk factor, and the risk of UTIs, including recurrent infections, increases over age sixty.
Menopause is believed to be a risk factor for recurrent UTIs for several reasons. Some of the main ones are the fact that low levels of estrogen impact the microbiomes in the vagina and the bladder, blood flow to the bladder and urethra decreases, and the cells in the urethra can become more fragile, which may make it easier for bacteria to attach. But there are likely many other factors.
Other non-menopause-related risk factors for recurrent UTIs are genetics (having a mother with recurrent UTIs increases the risk), a new sexual partner in the past year, incontinence, and age.
Vaginal Estrogen and Recurrent UTIs
Before we go further, it’s important to know that studies often use different endpoints. Two of the most common are the number of recurrent infections over a given time frame and the time to first infection. This can sometimes make it challenging to compare results between studies.
The first randomized clinical trial looking at vaginal estrogen for the prevention of UTIs was published in 1993 and enrolled 93 women and compared vaginal estriol