Successful placental removal guided by MRI-based mapping in advanced abdominal pregnancy: A case report and literature review

Advanced abdominal pregnancy is a rare but life-threatening condition associated with substantial maternal and fetal morbidity and mortality, particularly when diagnosis is delayed beyond the first trimester. Owing to its rarity, there is still no consensus regarding its optimal diagnostic approach or management. We present a case of advanced abdominal pregnancy in a woman who first sought medical care at 24 weeks' gestation. She reported five months of amenorrhea accompanied by progressively worsening abdominal pain, constipation, and dyspareunia. Ultrasonography demonstrated a gestational sac outside the uterine cavity. Magnetic resonance imaging was subsequently performed to define the placental location and its relationship to adjacent structures and to confirm the diagnosis of advanced abdominal pregnancy. Because the patient had persistent severe abdominal pain and clinical findings concerning for an acute abdomen, immediate surgical management was undertaken after counseling and preoperative planning. Laparotomy was performed through a midline abdominal incision. Intraoperatively, the omentum, uterus, adnexa, and bladder were densely adherent to the gestational sac, creating the appearance of a frozen pelvis. The placenta invaded the peritoneum overlying the sigmoid colon and left iliac region, although no major vascular involvement was identified. Organ-sparing surgery was successfully performed, and the placenta was carefully dissected and removed without complications. The postoperative course was uneventful, and the patient was discharged in good condition. Advanced abdominal pregnancy should be considered in the differential diagnosis of pregnant patients presenting with abdominal pain and atypical imaging findings. In symptomatic patients with an acute abdomen, immediate surgery may be preferred over expectant management. Although placental management remains controversial, detailed preoperative imaging is crucial for surgical planning. In selected cases without major vascular invasion, placental removal may be feasible with organ preservation.