Background <p>Choriocarcinoma coexisting with intrauterine pregnancy is extremely rare and necessitates early diagnosis.</p> Case presentation <p>A primigravida at 27⁺ weeks of gestation presented with a 3-day history of worsening abdominal pain. An ultrasound revealed a uterine mass, initially misdiagnosed as a degenerated uterine myoma. The correct diagnosis of a ruptured and bleeding fallopian tube choriocarcinoma was only made after a laparotomy which was prompted by patient’s significant abdominal hemorrhage and fetal death.</p> Conclusion <p>Acute abdomen and intra-abdominal hemorrhage during pregnancy should raise suspicion of choriocarcinoma.</p>