Estradiol vaginal tablets are the most appropriate treatment for this patient with genitourinary syndrome of menopause, indicated by her history of vaginal dryness, dyspareunia, and by pale mucosa with decreased rugae on physical examination, as well as the vaginal pH greater than 4.5. In menopausal women, low estrogen levels result in physiologic changes in the urogenital tissues that may result in genitourinary symptoms. The abnormal vaginal discharge is consistent with atrophic tissue friability.

Menopausal genitourinary symptoms that do not respond to vaginal lubricants are best treated with topical low-dose vaginal estradiol, which is available as vaginal tablets or a cream. Low-dose vaginal formulations are not absorbed systemically to a significant degree, and therefore, oral progestin is not needed when administering these topical agents. Estrogen-containing pliable polymer vaginal rings are also available, but only the low-dose ring is appropriate for treatment of menopausal genitourinary symptoms.

Bacterial vaginosis is commonly characterized by a malodorous thin gray discharge, with a positive whiff test and clue cells on saline microscopy. The absence of these findings argues against this diagnosis, and treatment for bacterial vaginosis with metronidazole vaginal gel would not be appropriate.

Miconazole vaginal cream is the treatment for vulvovaginal candidiasis. This patient did not have the white discharge and pruritus that are associated with a yeast infection, and the wet mount was negative for hyphae. Therefore, this would not be an appropriate treatment for this patient.

When genitourinary symptoms are the primary concern in a menopausal woman, low-dose vaginal estradiol is the therapeutic standard. Systemic hormone therapy can be used selectively to treat moderate to severe systemic vasomotor symptoms, but for this patient, systemic hormone therapy is not indicated.