Spontaneous Heterotopic Pregnancy with Tubal Rupture and Hemodynamic Instability, Followed by Delayed Intrauterine Miscarriage: A Case Report

Introduction: Spontaneous heterotopic pregnancy is a rare but potentially life-threatening condition, characterized by the simultaneous presence of an intrauterine and an ectopic gestation. Its diagnosis is challenging, particularly in patients without risk factors and in emergency settings where the presence of an intrauterine pregnancy may create a false sense of security. Case Presentation: We report the case of a 24-year-old nulliparous woman with no history of assisted reproduction who presented to the emergency department with severe abdominal pain and signs of hypovolemic shock. Physical examination revealed peritoneal irritation and hemodynamic instability. Transvaginal ultrasound demonstrated free fluid in the pelvis and a viable intrauterine gestational sac. Due to suspected obstetric acute abdomen, the patient underwent emergency exploratory laparotomy, which revealed a ruptured left tubal ectopic pregnancy with approximately 1500 mL of hemoperitoneum. A left salpingectomy was performed. Postoperatively, β-hCG levels initially declined but later rose, and follow-up ultrasound showed an intrauterine gestation without cardiac activity, consistent with missed abortion. Uterine evacuation was performed via manual vacuum aspiration without complications. Histopathology confirmed ruptured tubal ectopic pregnancy and intrauterine products of conception. The patient recovered favorably with multidisciplinary follow-up. Discussion: This case highlights the diagnostic difficulty of spontaneous heterotopic pregnancy, particularly in reproductive-age women without classic risk factors. The presence of an intrauterine pregnancy does not exclude the coexistence of an ectopic gestation. Hemodynamic instability and hemoperitoneum remain decisive criteria for urgent laparotomy, especially in low-resource settings where laparoscopic management may be limited. Conclusion: Spontaneous heterotopic pregnancy, although rare, should be considered in women presenting with acute abdomen, even when an intrauterine gestation has been confirmed. Early recognition, timely surgical intervention, and coordinated multidisciplinary management are essential to reduce maternal morbidity and mortality, particularly in facilities with limited diagnostic and surgical resources.