Clinical characteristics of women in reproductive age suffering from histologically proved adenomyosis: a single center retrospective cohort of 498 cases

Background
To characterize the population of women in reproductive age who benefit from a hysterectomy in terms of adenomyosis and endometriosis.

Methods
A retrospective single center study was performed on patients of reproductive age (≤ 45 years-old) who underwent hysterectomy for benign reasons between 2016 and 2022 in the Obstetrics and Gynecology Department at Liege University Hospital - Citadelle. Clinical data were collected from pathology and medical reports.

Results
A cohort of 498 patients, mostly Caucasian (73%), underwent a hysterectomy, at a mean age of 41 years (range 21- 45). Main surgical indications were chronic pelvic pain (CPP) (134/498, 27%), abnormal uterine bleeding (AUB) (172/498, 35%) or a combination of both symptoms (164/498, 33%). At the preoperative assessment, 171 (34%) of them presented endometriosis. Transvaginal ultrasound was performed in 351 cases and adenomyosis was accurately diagnosed in 66% of these patients. At the histological analysis, adenomyosis was found in 80% (401) of cases.

When we compared the population with histologically proved adenomyosis with the one without adenomyosis, we noticed that the presence of both concomitant AUB and CPP symptoms is more often expressed by women suffering from adenomyosis (respectively 141/401, 35% vs 23/97, 24%; p<0.05). Moreover, the sensitivity of ultrasound was higher for adenomyosis when both symptoms were present compared to when the patients suffered from CPP only (respectively 83/111, 75% vs 43/73, 59%; p<0.05). Patients with a diagnosis of endometriosis, pre- or post-operatively, presented more often adenomyosis than the others (147/171, 86 %). Focal Adenomyosis of the Outer Myometrium (FAOM) is more often found in patients with endometriosis (27/147, 18%, vs 10/254, 4%; p<0.05). Adenomyoma was found histologically in older women (42.4 vs 41.0 years, p <0.05). We did not notice any significant link between older age and a deeper invasion of the adenomyosis into the myometrium (p=0.08).

Conclusions
Women at reproductive age suffering from concomitant symptoms of chronic pelvic pain and AUB have a high probability of presenting adenomyosis. Moreover, endometriosis increases the risk of presence of concomitant adenomyosis.