Successful Treatment of a Pararenal Pregnancy Using High-Dose Methotrexate Regimen: A Case Report.

Background: Upper abdominal pregnancy is rare. Most patients present with hemoperitoneum, requiring emergency laparotomy.

Case: A 32-year-old woman presented with acute abdominal pain and an elevated beta-human chorionic gonadotropin (β-hCG) level. Ultrasound, computerized tomography (CT) scans, and laparoscopy failed to locate the source of elevated hCG. Subsequent positron emission tomography (PET)-CT demonstrated a cystic mass in the left pararenal region with no increased uptake. Repeated ultrasound scan revealed a live fetus implanted laterally to the abdominal aorta. After failing to respond to methotrexate at the usual dosage, a regimen used in gestational trophoblastic neoplasia was given. The pregnancy underwent miscarriage afterwards, and the hCG level gradually returned to normal.

Conclusion: The site of an ectopic pregnancy should be sought thoroughly to avoid missing an abdominal pregnancy and hence disastrous hemoperitoneum. While medical therapy with high-dose methotrexate is not a standard treatment, it can be considered after failing the traditional therapy, provided that there is adequate treatment monitoring and expertise in handling the side effects of the medication.