Superfetation after ovulation induction and intrauterine insemination performed during an unknown ectopic pregnancy.

This report describes the first case of superfetation after ovarian stimulation with gonadotrophins and intrauterine insemination (IUI) that were performed in the presence of an undiagnosed tubal pregnancy. A 32-year-old woman who underwent repeated attempts of ovarian stimulation and IUI was hospitalized for severe pelvic pain and submitted to laparoscopic salpingectomy because of ruptured salpynx containing a 6-week pregnancy. Transvaginal ultrasound examination showed a simultaneous intrauterine 2-week pregnancy that had been conceived by ovarian stimulation and IUI while the tubal pregnancy was already ongoing and still undiagnosed. The intrauterine pregnancy went on until term and ended with the spontaneous delivery of a healthy baby. This report demonstrates that human superfetation may occur after gonadotrophin treatment and IUI in the presence of an ongoing tubal pregnancy. It is recommended to perform a pregnancy test before starting ovulation induction even when an apparently normal blood discharge appeared.