Birth of monozygotic dichorionic twins after a single blastocyst embryo transfer: a case report of genetic determination of zygosity
Neli Semrl, M.D.,
Michael Barth, M.D.,
Sarah Feigl, M.D.,
Rüdiger Hochstätter, M.D.,
Irmgard Oreskovic, M.Sc.,
Herbert Fluhr, M.D., M.H.B.A.,
Philipp Klaritsch, M.D.,
Irene Speicher, M.D.,
Martina Kollmann, M.D., Ph.D.
Affiliations
Neli Semrl, M.D.
Department of Obstetrics and Gynecology, Medical University of Graz, Austria
Michael Barth, M.D.
Department of Obstetrics and Gynecology, Medical University of Graz, Austria
Sarah Feigl, M.D.
Department of Obstetrics and Gynecology, Medical University of Graz, Austria
Rüdiger Hochstätter, M.D.
Department of Obstetrics and Gynecology, Medical University of Graz, Austria
Irmgard Oreskovic, M.Sc.
Department of Obstetrics and Gynecology, Medical University of Graz, Austria
Herbert Fluhr, M.D., M.H.B.A.
Department of Obstetrics and Gynecology, Medical University of Graz, Austria
Philipp Klaritsch, M.D.
Department of Obstetrics and Gynecology, Medical University of Graz, Austria
Irene Speicher, M.D.
The Diagnostic and Research Institute of Pathology, Medical University of Graz, Austria
Martina Kollmann, M.D., Ph.D.
Department of Obstetrics and Gynecology, Medical University of Graz, Austria; Correspondence: Martina Kollmann, M.D., Ph.D., Department of Obstetrics and Gynecology, Medical University of Graz, Auenbruggerplatz 14 Graz 8036, Austria
Objective: To report a case of monozygotic dichorionic (DC) twins after a single cryopreserved blastocyst embryo transfer followed by genetic determination of zygosity postpartum. Design: Case report. Setting: University hospital. Patients: A 26-year-old woman with polycystic ovary syndrome and her 36-year-old male partner with severe oligozoospermia, resulting in a 1.5-year history of primary infertility. Interventions: Controlled ovarian stimulation and intracytoplasmic sperm injection treatment with single cryopreserved embryo transfer at blastocyst stage. Main Outcome Measures: Ultrasound images of the fetuses and short tandem repeat genotyping postpartum. Results: A DC twin pregnancy following a single cryopreserved blastocyst embryo transfer was confirmed at the first trimester screening. Confirmatory testing performed postpartum included short tandem repeat analysis determining monozygosity and pathology examination reporting DC placental configuration. Conclusions: Dichorionic monozygotic twins are thought to arise from the splitting of an embryo before the blastocyst stage. This case suggests that placental configuration of monozygotic twins may not strictly depend on timing of embryo division. Genetic analysis is the only tool to confirm the zygosity.
