Osseous metaplasia of the endometrium: A multicenter retrospective study

To describe clinical and demographic characteristics, ultrasound appearance, and hysteroscopic outcomes of patients with endometrial osseous metaplasia.

We conducted a multicenter retrospective study. We retrospectively reviewed the medical records of all consecutive patients who were referred for hysteroscopy at fourteen institutions in Venezuela, Spain, Morocco, India, Ukraine, Argentina, the United States, and Italy between 1994 and 2018. We identified and included all patients who had a diagnosis of osseous metaplasia at the pathologic report, and data were retrieved from the medical records.

Between January 1st, 1994, and December 31st, 2018, 63 patients out of a total of 419,673 women who underwent hysteroscopy had a diagnosis of osseous metaplasia (0.015%). Most patients were 31-40 years old (53.7%), were Caucasian or Hispanic (95.5%), and had at least one previous pregnancy (86.9%). Forty-one out of 63 patients (65.1%) had at least one miscarriage before the index hysteroscopy. Dysmenorrhea, abnormal uterine bleeding, and infertility were reported by 34.9%, 27.0%, and 23.8% of patients. 14.3% of women were asymptomatic. Preoperative transvaginal ultrasound was available and identified a hyperechoic area of variable size with posterior acoustic shadowing in all cases. Hysteroscopy was successful without complications in all 63 cases. Follow-up data were available in 30.2% of patients: 69.2% of patients were infertile, and 44.4% of them conceived and achieved a live birth; all other symptoms improved after hysteroscopic treatment in all patients.

Osseous metaplasia appears associated with multiple unspecific gynecologic symptoms without the predominant role of infertility, as previously suggested. Although endometrial osseous metaplasia is rare, gynecologists should consider this pathologic condition when the characteristic ultrasound appearance is detected, being hysteroscopic treatment effective.