Cryoloop vitrification of human day 3 cleavage-stage embryos: post-vitrification development, pregnancy outcomes and live births.
Vitrification technology has shown great promise for cryopreservation of human embryos. The majority of this work has been with blastocyst-stage embryos. This report describes initial clinical results following vitrification of human embryos on day 3 of culture at the 6- to 8-cell stage. A total of 236 embryos were cryopreserved on cryoloops using a vitrification protocol. Warmed embryos were cultured until day 5 before transfer to the patient. The post-warming survival rate was 85%. The clinical pregnancy rate was 44% (34/77), and the implantation rate was 20% (40/201). In transfers where at least one warmed embryo reached the blastocyst stage by the day of transfer, the clinical pregnancy rate was 58% (28/48). The cryoloop was an excellent vessel for ultra-rapid cryopreservation of embryos. This study supports the effectiveness of a dimethylsulphoxide/ethylene glycol cryoprotectant combination for vitrification of human embryos at the 6- to 8-cell stage.
Desai
Nina
N
Cleveland Clinic Fertility Centre/Cleveland Clinic Foundation, Beachwood, OH 44122, USA. desain@ccf.org
Blackmon
Heather
H
Szeptycki
Julia
J
Goldfarb
James
J
D000328:Adult; D015925:Cryopreservation / Q000295:instrumentation / Q000379:methods*; D046149:Embryo Culture Techniques; D004622:Embryo, Mammalian / Q000166:cytology; D047108:Embryonic Development; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome