The effect of sexual activity on vaginal atrophy was investigated in a group of 52 postmenopausal women (mean age, 57 years). Subjects were divided into two groups: sexually active (intercourse frequency, three or more times monthly) and sexually inactive (intercourse frequency, less than ten times yearly). Two gynecologists examined all subjects and completed an index of vaginal atrophy that assessed six genital dimensions. Blood samples were also analyzed by radioimmunoassay for levels of circulating estrone, estradiol, androstenedione, testosterone, follicle-stimulating hormone, and luteinizing hormone (LH). As predicted, less vaginal atrophy was apparent in the sexually active women as opposed to the sexually inactive women. Further, women with less vaginal atrophy had significantly higher mean levels of androgens (androstenedione and testosterone) and gonadotropins (particularly LH). We discuss herein the implications of this study, particularly the importance of androgens in reducing atrophy and maintaining sexual interest.