Gross deciduosis peritonei obstructing labor: a case report and review of the literature.

Gross deciduosis peritonei is a rare lesion characterized by the presence of grossly visible peritoneal decidual tissue in pregnant women; we present the clinicopathologic features of one such case. A 24-year-old, G4P1A2, Hispanic female underwent cesarean section at 39 weeks' gestation for dystocia related to pelvic masses. Multiple, light tan peritoneal masses involved the cul-de-sac, both ovaries, pelvic wall, omentum, and the large and small bowel. The intraoperative appearance suggested peritoneal carcinomatosis. A right ovarian mass was excised and biopsies were obtained from other sites. Microscopic examination showed the typical features of decidua in all of the lesions. Two weeks postoperatively, the patient was admitted with nausea and vomiting suggestive of a small bowel obstruction, which resolved after 2 days of medical treatment. After a postpartum visit at 5 weeks, the patient was lost to follow-up.