Hemoperitoneum as a precursor of deep pelvic endometriosis: a cohort study

OBJECTIVE: To determine whether significant hemoperitoneum could be a precursor of deep pelvic endometriosis in non-pregnant premenopausal women presenting with severe acute lower abdominal pain. METHODS: This was a prospective observational cohort study carried out at a dedicated gynecological diagnostic unit over a period of 18 months. We included consecutive non-pregnant, premenopausal women who attended with severe acute lower abdominal pain and underwent a pelvic ultrasound examination. Women were triaged for surgical or conservative management depending on the cause of pain and severity of their symptoms. Those who were selected for conservative management were invited for follow-up ultrasound scans. The main outcome measure was evidence of newly developed deep endometriosis at follow-up examination. RESULTS: Of 118 non-pregnant women who attended our unit with severe acute lower abdominal pain, 20 underwent emergency surgery and 17 had a history of endometriosis, or evidence of endometriosis on the initial scan, and were excluded from the study. Therefore, conservative management was employed in 81 women, eight of whom had evidence of significant hemoperitoneum at presentation. A total of 35 women attended for all follow-up ultrasound scans. At the completion of follow-up, four of six (67% (95% CI, 22-96%)) women who presented initially with significant intra-abdominal bleeding had developed new evidence of deep endometriosis, compared with one of 29 (3% (95% CI, 0-18%)) of those without hemoperitoneum (relative risk, 19.3 (95% CI, 3-144); P < 0.001). CONCLUSION: In some women, the presence of significant hemoperitoneum that is managed conservatively precedes the development of deep endometriosis. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.