Objectives: Acute abdomen in pregnancy can be due to gynaecologic, gastrointestinal, genitourinary or vascular pathologies. Diagnosis can be challenging especially in the 3rd trimester due to the gravid uterus occupying almost 2/3rds of the abdominal cavity. Imaging is beneficial in aiding with diagnosis. However there are limitations to the imaging modalities due to the advanced stage of pregnancy. Clinical acumen and surgical intervention is the mainstay in intervention and management.
Method: We demonstrate a case of acute abdomen presenting in the third trimester of pregnancy. Surgical intervention for suspicion of acute appendicitis revealed a ruptured ovarian endometrioma resulting in haemoperitoneum.
Case Report: A 32 year old primigravida at 31 weeks gestation presented with symptoms of sudden onset abdominal pain. She had no fever, bowel or urinary symptoms. There were no contractions and fetal movement was good. Clinically she was stable, abdomen soft with tenderness at umbilical and right iliac fossa but no signs off peritonism. Ultrasound abdomen reported mild to moderate intraabdominal fluid collection mainly at the right iliac fossa. The next day her condition did not improve and she became tachycardic. Surgical team proceeded with laparotomy for acute appendicitis. On entering the peritoneal cavity, there was haemoperitoneum and a white appendix. The Lanz incision was closed and proceeded with a midline laparotomy. Upon exteriorising the gravid uterus, the true pathology was seen. It was a ruptured left endometrioma adherent to the posterior uterine wall, with bleeding vessels from the cyst wall and raw areas. As the ruptured cyst was situated near the Pouch of Douglas and access was restricted; Caesarean section was performed and a baby weighing 1,750 gm was delivered. The bleeding cyst wall vessels were ligated and hemostasis secured. Haemoperitoneum was 1 litre. Post operatively she had an uneventful recovery.
Conclusion: Ruptured ovarian endometrioma is rare in pregnancy but should be entertained as a differential in acute abdomen presenting in pregnancy.