Diagnostic Pitfall: Intrauterine Pseudogestational Sac Mimicking an Anembryonic Pregnancy in Tubal Ectopic Pregnancy...

Ectopic pregnancy is a potentially life-threatening condition, and its diagnosis may be complicated when an intrauterine pseudogestational sac mimics a nonviable intrauterine pregnancy. This diagnostic pitfall can lead to mismanagement and delay in appropriate treatment.

A case of a 33-year-old woman (G4P2A1) at 9-10 weeks of gestation presenting with vaginal bleeding. Ultrasonography revealed an intrauterine sac suggestive of blighted ovum and a concomitant adnexal mass suspicious for ectopic pregnancy. Curettage was performed, yielding tissue that on histopathology showed endometrial hyperplasia without chorionic villi, consistent with a pseudogestational sac. Subsequent exploratory laparotomy revealed a right tubal abortion, and right salpingectomy was performed. Histopathological examination confirmed chorionic villi within hemorrhagic tissue. The postoperative course was uneventful, and the patient was discharged in good condition.

This case highlights the diagnostic challenge of differentiating a pseudogestational sac from a nonviable intrauterine pregnancy in ectopic pregnancy. A sac-like intrauterine structure alone is insufficient to confirm intrauterine pregnancy, and accurate diagnosis requires integration of serial β-hCG assessment, repeat transvaginal ultrasonography, and histopathological evaluation. Awareness of this diagnostic pitfall is essential to avoid unnecessary uterine intervention and ensure timely, appropriate management.