Ectopic pregnancy occupies a significant place in the structure of causes of maternal mortality. Timely diagnosis is even more complicated when there is a combination of both uterine and ectopic localization of the ovum. The article describes the clinical observation of heterotopic pregnancy, features of the clinical picture, diagnostic search and treatment strategy. The possibility of preservation of intrauterine pregnancy after surgical removal of a pathologically located second fertilized ovum has been shown. The patient was admitted to the gynecological department with complaints of bleeding from the genital tract against the background of delayed menstruation. An ultrasound examination revealed the presence of dichorionic diamniotic twins, with one fertilized egg localized in the interstitial part of the fallopian tube stump. Surgical removal of the stump with the fertilized egg was performed. The intrauterine pregnancy was preserved. Thus, with timely diagnosis of heterotopic pregnancy and adequate tactics, it is possible to maintain intrauterine pregnancy.