The Incidence of Dichorionic Diamniotic Twin Pregnancy After Single Blastocyst Embryo Transfer and Zygosity: 8 Years of Single-Center Experience.
Dichorionic diamniotic (DCDA) twin pregnancies after single blastocyst embryo transfer have been reported recently, although a blastocyst ovum is generally believed to divide into monochorionic twin pregnancy. We investigated the incidence of DCDA twin pregnancy after single blastocyst embryo transfer and their zygosity. This prospective cohort study included 655 consecutive twin pregnancies that were managed from 2006 to 2014 at our institution. Chorionicity and amnionicity were determined using first-trimester ultrasonography and/or placental pathology. Zygosity was analyzed if the cases were DCDA twins after single blastocyst embryo transfer. Among 655 twin pregnancies, there were 348 DCDA cases, 295 monochorionic diamniotic (MCDA) cases and 12 monochorionic monoamniotic cases. Single blastocyst embryo transfer was performed in 43 cases. Six out of the 43 (14%) cases involved DCDA twin pregnancies and the other 37 cases involved MCDA twin pregnancies. Three DCDA twins born after single blastocyst embryo transfer, wherein frozen embryo transfer (FET) was performed in the natural cycle, were dizygotic, and the other three cases, wherein FET with hormone replacement therapy was performed, were monozygotic. DCDA twin pregnancy occurred in 14% (7% for monozygotic and 7% for dizygotic) of twin pregnancies after single blastocyst embryo transfer cases.
['Konno|Hiroko|H|', 'Murakoshi|Takeshi|T|', 'Miura|Kiyonori|K|', 'Masuzaki|Hideaki|H|']
D000328:Adult D000650:Amnion D001755:Blastocyst D002823:Chorion D015331:Cohort Studies D004624:Embryo Transfer D005260:Female D006801:Humans D011247:Pregnancy D011261:Pregnancy Trimester, First D011446:Prospective Studies D014429:Twins, Dizygotic D014430:Twins, Monozygotic D016216:Ultrasonography, Prenatal
single blastocyst embryo transfer dizygotic monozygotic Monozygotic dichorionic diamniotic twin monochorionic diamniotic twin