Clinical features of patients with previous spontaneous rupture of ovarian endometrioma operated electively: a case-control study

BACKGROUND: The aim of the study is to investigate the proportion and clinical features of previous spontaneously ruptured ovarian endometrioma among women who underwent elective surgery for endometrioma. METHODS: This retrospective study was based on a cohort of elective surgeries for endometrioma performed by the same gynecologic team at Peking Union Medical College Hospital from January 2017 to October 2022. Patients diagnosed with previous spontaneously ruptured endometrioma during elective surgery were enrolled in the ruptured group. In the same cohort, patients with unruptured endometrioma treated during the same period were selected as the unruptured group by 1:2 matching according to age. Demographic and clinical information were collected and compared between two groups. RESULTS: A total of 422 patients in the cohort were diagnosed with endometrioma. There were 38 patients (9.0%) in ruptured group and 76 patients in unruptured group. All enrolled participants were treated by laparoscopic surgery. In ruptured group, 86.8% patients had a history of acute abdominal pain, which was only 13.2% in unruptured group (P < 0.001). Compared to unruptured group, patients diagnosed with ruptured endometrioma had a lower BMI (P = 0.021), larger maximum diameter of endometrioma (P = 0.040), higher proportion of cul-de-sac partial obliteration rather than complete obliteration (P = 0.003). CONCLUSIONS: Spontaneous rupture of endometrioma is not rare. The proportion of spontaneous rupture of endometrioma in our study was higher than that reported in the literatures. In women with endometrioma, the onset of acute abdominal pain should be considered a rupture of cyst, especially in patients with big cysts.