Effects of estrogen on vaginal physiology
As many of the symptoms of vaginal atrophy are associated with estrogen deficiency, improvements can be observed following estrogen-replacement therapy. A review of clinical trials of estrogen use in menopausal women found that different types of estrogen therapy were associated with increased frequency of sexual activity, enjoyment, desire, arousal, fantasies, satisfaction, vaginal lubrication, feeling physically attractive, and reduced dyspareunia, vaginal dryness, and sexual problems.6 In a meta-analysis of five randomized clinical trials, data suggested that estrogen therapy provided a beneficial effect in the prevention of recurrent UTIs.14 The average number of UTIs was significantly less (P=0.01) when treated with estrogen compared with placebo, with a significantly different odds ratio for the use of vaginal estrogen (P=0.008) compared with oral administration of estrogen.14
Cytologic and physiologic changes were observed in vaginal tissues following the use of hormone replacement therapy. In one study, atrophic changes were observed in cervical smears in 46.6% of nonestrogen users but only 1.66% of estrogen users.15 Specifically, 46% of patients not using estrogen therapy had a predominance of parabasal cells (>70%), while 75% of estrogen-treated women had a low percentage of parabasal cells and a predominance of intermediate cells. In another study, an increase in intermediate and superficial cells was observed one month after initiation of treatment in estrogen-treated postmenopausal women, but no cytological differences were observed in the placebo group.16 In both studies, the estrogen-treated patients had a significantly higher proportion of lactobacilli in the vaginal flora compared with nonusers.15,16 Additionally, the vaginal pH of estrogen-treated postmenopausal women was observed to be significantly lower (P <0.01) compared with that of placebo-treated women for up to 90 days after initiation of therapy.16
Symptoms of vaginal atrophy are generally progressive over time due to the natural decline of estrogen levels with age, and they will not resolve without treatment. It is important to identify signs and symptoms associated with vaginal atrophy so a timely diagnosis can lead to implementation of an appropriate treatment strategy. Nonhormonal and hormonal treatment options should both be considered based on an assessment of the individual patient’s needs.
Vaginal atrophy symptoms observed in menopausal women include vaginal dryness, itching, discharge, pain, and dyspareunia, which may be accompanied by such irritating urinary symptoms as frequency, urgency, and burning.2,7 Following an initial diagnosis of suspected vaginal atrophy, the vulva, labia, vaginal epithelium, and urethral tissues should be visually observed for dryness, thinning, pale color, loss of rugae, lack of shiny vaginal secretions, sites of trauma in the vestibule and vagina, atrophy of the labia, reduced pelvic floor skeletal muscle tone, and pain-triggering spots.2,5
In addition to visual examination, certain laboratory markers may prove useful in objectively characterizing vulvovaginal symptoms. Measurement of vaginal pH can easily be accomplished using a pH indicator strip (premenopausal pH = 3.5-4.5; postmenopausal pH = 5.0-7.0).1,7 The vaginal maturation index, which can be performed in the office, is a ratio of parabasal, intermediate, and superficial squamous cells isolated from the upper third of the vagina. Generally, a predominance of parabasal and intermediate cells is found during menopause (Figure 1).2,4,17 A vaginal health index is a useful tool that provides objective information by which to identify the severity of vaginal symptoms in order to assist with selection of an appropriate course of treatment (Table 1).7