In this large, population-based cohort of community-dwelling postmenopausal women, nearly half of women reported at least “a little” problem with one or more vaginal symptoms, and nearly 20% of women reported at least “a moderate” problem. Of those women reporting problematic vaginal symptoms at baseline, approximately half were asymptomatic after 24 months without using estrogen therapy. These findings indicate that although vaginal symptoms such as dryness, itching, and painful sexual intercourse are a significant problem for a large proportion of women for many years after menopause, they may resolve in up to half of women even in the absence of estrogen supplementation.
Very little is known about the natural history of symptoms such as vaginal dryness, itching, and painful intercourse during the postmenopausal years. Although the physical changes associated with vaginal atrophy are thought to persist as women age, it may be that these changes cease to cause bothersome symptoms in some older postmenopausal women. Possible explanations for attenuation of women’s symptoms over time include stabilization of acute fluctuations in women’s sex hormone levels, up-regulation of sex hormone receptors in vaginal tissue, changes in sexual practices or toileting habits that reduce the severity of vaginal symptoms, and other changes in women’s day-to-day activities such as physical exercise that may affect women’s experience of vaginal dryness and itching.
We found that diabetes was significantly associated with multiple vaginal symptoms in this cohort, independent of vaginal pH or colonization with C. albicans. This finding suggests that diabetes may influence the development and/or severity of vaginal symptoms after menopause through mechanisms other than alteration of the vaginal bacterial milieu. Other potential reasons for the increased prevalence among diabetic women include changes in the vagina due to functional vascular changes, neuropathy, or tissue glycosylation related to diabetes and side effects from diabetic medications. In addition, women may be more likely to perceive their vaginal symptoms as being more problematic or burdensome in the setting of a comorbid chronic health condition, a possibility that is supported by our additional finding that lower overall physical functioning was also associated with self-reporting of these symptoms.
Lower body mass index also emerged as a risk factor for more than one vaginal symptom in our study, independent of age and physical function status. Women with lower body mass index are thought to have lower circulating estrogen levels due to decreased adipocyte-based aromatization of estrone and conversion of androstenedione to estrone.15
However, previous studies involving primarily middle-aged women have not found a significant relationship between body mass index and symptoms of vaginal dryness16
and further research is needed to confirm the relationship between body mass index, estrogen levels, and vaginal symptoms in postmenopausal women.
Although we detected associations between vaginal pH and painful sexual intercourse, as well as between vaginal enterococcus colonization and vaginal dryness, vaginal physical assessments were not the dominant predictors of vaginal symptoms in our study. A previous study of postmenopausal women also found only weak correlations between self-reported vaginal symptoms and physical examination parameters such as vaginal pH.18
Taken together, these findings suggest that contextual and behavioral factors may play a greater role in a woman’s subjective experience of vaginal symptoms than purely physical signs of atrophy or inflammation.
Although oral estrogen use was associated with decreased reporting of vaginal symptoms in this cohort, vaginal estrogen use was associated with increased symptom reporting. We expect that the latter finding was the result of confounding by indication (ie, women with more severe vaginal symptoms were more likely to be prescribed vaginal estrogen) rather than a reflection of the true clinical effect of vaginal estrogen therapy on vaginal symptoms, given that the beneficial effect of vaginal estrogen on vaginal atrophy symptoms has been established in randomized controlled trials where confounding by indication is not an issue.19,20
To date, there have been relatively few population-based studies of vaginal symptoms in postmenopausal women. A recent analysis of women in the combined US-based Women’s Health Initiative observational study and clinical trials reported that 27% of women had problems with vaginal dryness and 19% had irritation or itching,21
whereas a survey of women aged 61 years living in Uppsala County, Sweden, found that 43% had difficulty with vaginal dryness and 10% had difficulty with vaginal burning.22
In contrast, a study of postmenopausal women 55 years and older living in Great Britain found that only 8% reported dryness and 11% had itching.23
None of these studies followed women longitudinally over time to assess the natural history of their symptoms, however, and only the Women’s Health Initiative study examined symptoms by years since menopause.
This study benefits from a large, community-dwelling cohort of women, repeated assessment of vaginal symptoms over time, and evaluation of a variety of covariates with the potential to affect women’s urogenital function. Nevertheless, several important limitations of this study should be noted. First, vaginal symptoms were assessed primarily by interviewer-administered questionnaire, and it is possible that some participants may have been uncomfortable acknowledging vaginal dryness, itching, or painful intercourse because of the sensitive nature of these symptoms. However, one symptom, painful intercourse, was also assessed by daily diaries that women completed at home, and we were able to confirm that reporting of painful intercourse by questionnaire was significantly associated with reporting of painful intercourse by diary in the baseline month (P < 0.001). For example, among women who reported having “a lot” of problems with painful intercourse on their baseline questionnaires, 30% reported at least one episode of painful intercourse by diary in the month immediately after their baseline visit, compared with less than 1% of women who indicated that they were “not at all” bothered by painful intercourse on their baseline questionnaires. Second, participants in this study did not undergo focused diagnostic evaluation for their vaginal dryness, itching, or dyspareunia, and we are therefore unable to confirm the specific etiology of their vaginal symptoms. Some of the women’s symptoms of itching or pain could have been caused by conditions such as vulvovaginal lichen planus that would not be expected to respond to estrogen therapy.
In addition, although our study sample was enriched with diabetic women, we adjusted our estimates of the baseline prevalence of vaginal symptoms to take into account this sampling frame. Our finding that diabetes was associated with increased risk of problematic vaginal symptoms independent of vaginal microbial factors raises intriguing questions about the potential relationship between diabetes, vaginal atrophy and inflammation, and symptom reporting in older women.