title: Heterotopic pregnancy after a single embryo transfer.
abstract: Heterotopic pregnancy is a rare and life-threatening condition which is defined as coexistent intrauterine and ectopic gestation. The risk of ectopic and heterotopic pregnancy is increasing due to the increased risk of multiple pregnancies with the aid of assisted reproductive technologies. However, it hardly happens in the setting of single embryo transfer, since single embryo transfer significantly reduces the incidence of multiple pregnancies. Surprisingly, we experienced a case of heterotopic pregnancy after a single embryo transfer caused by coincidental natural pregnancy during assisted reproductive technologies. An infertile woman who underwent, during her natural cycle, transfer of a single embryo that had been cryopreserved for 3 years was found to be heterotopically pregnant. After an early and successful management with laparoscopic right salpingectomy, she finally reached at full-term vaginal delivery.
authors.affiliation: Department of Obstetrics and Gynecology, Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Ji Sun
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Obstetrics and Gynecology, Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Hyun-Hwa
authors.initials: HH
authors.lastname: Cha
authors.affiliation: Department of Obstetrics and Gynecology, Konyang University Hospital, Konyang University School of Medicine, Daejeon, Korea.
authors.forename: Ae Ra
authors.initials: AR
authors.lastname: Han
authors.affiliation: Maria Fertility Clinic, Daegu, Korea.
authors.forename: Seong Goo
authors.initials: SG
authors.lastname: Lee
authors.affiliation: Department of Obstetrics and Gynecology, Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Won Joon
authors.identifier: 0000-0002-8088-2554
authors.initials: WJ
authors.lastname: Seong
keywords: Assisted reproductive techniques; Heterotopic pregnancy; Single embryo transfer