Effect of local conjugated estrogens on vaginal pH in elderly women

The decline in estrogens during and after menopause is associated with an increase in vaginal pH and an increased susceptibility to urinary tract infections (UTIs). Decreased vaginal pH following short-term treatment with topical estrogens may reduce the incidence of such infections. This study was undertaken to evaluate the effect of low-dose, topical conjugated estrogens vaginal cream (CEVC) on vaginal pH in older, postmenopausal women.

We conducted a retrospective analysis of initial and follow-up evaluations of older, postmenopausal women residing in 19 long-term care facilities who were referred to Seton Health System's Incontinence Treatment Center between January 2, 1997, and June 13, 1998. Patients were untreated or were administered conjugated estrogens intravaginally (0.5 g/d, 3 days per week).

Incontinence Treatment Center, Seton Health System.

Two hundred fifty-eight postmenopausal women (mean age 83 years), residents of skilled nursing facilities, who were diagnosed with urinary incontinence, were included in the study.

Measurements included age, CEVC treatment, vaginal pH, and history of UTIs or hysterectomy.

In the CEVC-treated women, vaginal pH was reduced from a mean of 7.41 +/- 0.71 to 6.80 +/- 0.70 after 6 weeks (n = 213; P = 0.0001). No differences in vaginal pH were observed in untreated women (n = 45). Continuation of CEVC treatment for an additional 6 weeks (n = 93) resulted in further decreases in vaginal pH (P = 0.017). Women who discontinued treatment after 6 weeks maintained a lower vaginal pH for 6 weeks (P = 0.0004), and there was no significant difference between groups at Week 12.

Low-dose CEVC for 6 and 12 weeks reduces vaginal pH in older women residing in long-term care facilities. The decreased vaginal pH following short-term treatment with topical estrogens may reduce the incidence of recurrent UTIs.