Why Are UTIs More Common After Menopause?

Estrogen depletion alters the vaginal epithelium, with distinct im pairments in lubrication, elasticity, pH, and blood flow. Pubic hair becomes scant, the vaginal epithelium becomes pale and dry, and the labia minora recede or fuse. Furthermore, the vaginal microbiome changes, with increasing pH following menopause and loss of lactobacillus predominance. These alterations allow a more hospitable en vironment for bacterial growth and increase the risk of UTI. Estrogen may also play a role in urothelial health as well as in the autonomic and sensory innervation of the vagina.

Recurrent UTIs are very common in postmenopausal women. The use of vaginal estrogen therapy is both safe and efficacious in lowering UTI risk. Vaginal estrogen increases the presence of lactobacillus in the vagina in postmenopausal women. The 2019 American Urological Association guideline for recurrent uncomplicated UTIs in women recommends that clinicians offer vaginal estrogen therapy to peri- and post-menopausal women with recurrent UTIs to reduce their risk. In addition, the guideline recommends vaginal estrogen therapy for women already on systemic HRT without an increased risk of adverse events with the added vaginal estrogen use. Systemic HRT has not been shown to improve risk of recurrent UTIs. Several randomized controlled trials of various applications of vaginal estrogen therapy have shown a decreased incidence and time to recurrence of UTIs in hypoestrogenic women. These studies did not identify any form of vaginal estrogen as clearly superior in reducing UTI risk or treating GSM symptoms. Thus, the choice of vaginal estrogen formulation should be according to patient preference.