The incidence of heterotopic/ectopic pregnancy has risen in recent years, largely
due to more frequent use of ovulatory medicine and increased incidence of pelvic inflammatory
disease. In a natural cycle, it is a very rare event. Most heterotopic/ectopic pregnancies
are localized in the uterine tube and, usually, it is diagnosed when symptoms develop.
We report the case of a 37 year-old, gravida 2, para 0, abortion 1 woman with no known
risk factors for heterotopic pregnancy. The patient attended the emergency department
because of acute abdominal pain. She was evaluated in our department and a heterotopic
twin pregnancy in the tube was diagnosed by transvaginal sonography. Intrauterine
pregnancy with positive fetal cardiac activity at 9 weeks of gestation according to
crown-rump length measurement was detected. Laparotomy was carried out because of
acute abdominal syndrome. Right ruptured tubal ectopic/heterotopic pregnancy and hemoperitoneum
were diagnosed. Right salpingectomy was carried out. Pathology revealed monochorionic
twin tubal pregnancy. In a review of the literature, this is first case of twin tubal
pregnancy in one uterine tube. In conclusion, heterotopic pregnancy in twin form in
the uterine tube is possible in natural cycles. Intrauterine pregnancy does not exclude
extrauterine pregnancy in natural cycles.