Adenomyosis a Variant, Not a Disease? Evidence From Hysterectomized Menopausal Women in the Study of Women’s Health Across the Nation (SWAN)

Adenomyosis, a nonmalignant condition of the uterus, is a common diagnosis in hysterectomy specimens from women undergoing the perimenopausal transition. Its diagnosis is often used as an indication for hysterectomy and a number of medical and surgical treatments are now being recommended. Its incidence varies widely, ranging from 8.8% to 61.5%. Symptoms associated with adenomyosis include uterine bleeding, chronic pelvic pain, fibroids, and endometriosis. Several investigators, however, believe that these associations are nonspecific, and have challenged the view that adenomyosis is a specific disease. The aim of this study was to determine the incidence of adenomyosis in hysterectomy specimens and assess the association of adenomyosis with uterine fibroids, endometriosis, abnormal uterine bleeding, and chronic pelvic pain in women undergoing the menopausal transition. This retrospective cohort study is part of an 11-year study, the Study of Women’s Health Across the Nation (SWAN), which is a multi-ethnic, multi-site community-based study of women in the menopausal transition. A total 3102 cohort women enrolled in SWAN completed a follow-up visit over the 9 years and records were obtained for 137 women containing information on histologic pathology. Among the 137 women with histologic findings, adenomyosis was found in 66 (48%) and was absent in 77 (52%). No statistically significant difference was found in frequencies of the presenting symptoms between women with or without adenomyosis. There was no difference in the percentage of women with and without adenomyosis among those with fibroids (37% versus 43%), endometriosis (3% versus 5%), abnormal bleeding (27% versus 33%), or chronic pelvic pain in the presence of fibroids (12% versus 17%). The investigators conclude from these findings that adenomyosis may be an incidental finding and a normal variant unrelated to symptomatology.