Understand rates of pathology confirmed adenomyosis occurring in the setting of endometriosis and identify predictive factors for the diagnosis of adenomyosis.

Retrospective cross-sectional study of patients undergoing concurrent hysterectomy and excision of pathology confirmed endometriosis over a two-year period. Patients without pathology confirmed endometriosis were excluded. Six full-thickness uterine sections for histologic analysis was performed to thoroughly evaluate for adenomyosis.

A total of 95 patients with pathology confirmed endometriosis were identified that also underwent hysterectomy during the study period. Adenomyosis was pathologically noted in 53 individuals (55.8%; CI: 45.2%, 66.0%).The primary indications for hysterectomy were pelvic pain (78.9%), heavy menstrual bleeding (37.9%), and endometriosis (24.2%). Significant factors included age [adenomyosis: 40.9 years (SD = 7.1) vs no adenomyosis: 38.1 years (7.4)] ( p = 0.026), dyspareunia (52.9% vs 81.0%; p = 0.006) and prior dilation and curettage (D & C) (24.5% vs 9.5%; p = 0.039). There were no statistically significant differences in parity, uterine weight, endometriosis stage, or history of cesarean section, laparotomy, or laparoscopy in those with or without adenomyosis. After adjusting for age, ethnicity, and imaging type, patients with prior D & C were 4.6 times at risk of having adenomyosis (OR: 4.6; CI: 1.19, 23.5). However, patients with dyspareunia were less likely to have adenomyosis (OR: 0.21; CI: 0.06, 0.61).

In this population, 45.2% did not have coexisting adenomyosis. Despite overlapping symptomology between endometriosis and adenomyosis, unique clinical factors, such as prior D&C and absence of dyspareunia, were found to be predictive of adenomyosis.