Unilateral twin tubal pregnancy and subsequent heterotopic pregnancy in a patient following in vitro fertilization.

Unilateral twin tubal gestations are extremely rare with a reported incidence of 1 per 200 ectopic pregnancies. In recent years, the incidence of heterotopic pregnancy associated with in vitro fertilization and embryo transfer (IVF-ET) has risen to 1%-3% of achieved pregnancies. We report a very rare case of a 32-year-old woman with 6-year primary infertility with unilateral twin tubal pregnancy and subsequent heterotopic pregnancy following two IVF treatments. Her gynecologic history was notable for previous distal occlusion of the left fallopian tube treated by laparoscopic reconstructive surgery. After ovulation induction and IVF with ET of two embryos, transvaginal sonography at 6 weeks revealed two separate gestational sacs in the left adnexal mass. Emergency laparoscopy showed unruptured ampullar pregnancy and salpingectomy was carried out. On second IVF two years later, after ovulation induction and ET of three embryos, endovaginal sonography at 6 weeks revealed only one intrauterine sac. One week later, the patient complained of intermittent episodes of lower abdominal pain in the right quadrant. Ultrasound confirmed intrauterine pregnancy and revealed right tubal gestational sac. Laparoscopy showed unruptured right ampullar pregnancy and salpingectomy was performed. Histology of salpingectomy specimens showed signs of chronic infection in both tubes. The intrauterine pregnancy progressed to term when a healthy infant was delivered vaginally. Gynecologists should always consider the possibility of ectopic pregnancy in pregnancies following IVF-ET, particularly in cases with tubal disease and abdominal pain.