title: High survival and hatching rates following vitrification of embryos at blastocyst stage: a bovine model study.
abstract: Cryopreservation of embryos at the blastocyst stage may provide an effective method to increase the cumulative pregnancy rate for each treatment cycle of ovarian-stimulated IVF. The objective of this study was to evaluate the survival rate and hatching rate of bovine blastocysts following vitrification using a method designed for oocytes, with a view to introducing this methodology into human assisted reproduction technology and reproductive medicine. Bovine blastocysts were produced from abattoir materials subjected to in-vitro maturation and in-vitro fertilization. Survival rate of the bovine blastocysts was 100% (94/94) following vitrification using a method designed for oocyte cryopreservation. There was no difference in the hatching rate of the bovine blastocysts between control (62.5%: 60/96) and vitrified (61.7%: 58/94) groups. The number of dead cells in the blastocysts was not significantly different between control (5.0 +/- 2.9) and vitrified (9.5 +/- 4.0) groups. In conclusion, the results of this study indicate that bovine blastocysts can be vitrified successfully using a procedure designed for oocyte cryopreservation. It is possible that this method may also be successful for the cryopreservation of human embryos. A further study into this is currently being organized.
authors.affiliation: Department of Obstetrics and Gynecology, McGill University, Montreal, Canada H3A 1A1.
authors.forename: Jack Y J
authors.initials: JY
authors.lastname: Huang
authors.forename: Jin-Tae
authors.initials: JT
authors.lastname: Chung
authors.forename: Seang Lin
authors.initials: SL
authors.lastname: Tan
authors.forename: Ri-Cheng
authors.initials: RC
authors.lastname: Chian
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology* / Q000378:metabolism; D002417:Cattle; D002470:Cell Survival; D015925:Cryopreservation / Q000379:methods*; D053938:DNA Fragmentation; D046149:Embryo Culture Techniques; D004622:Embryo, Mammalian / Q000166:cytology*; D005260:Female; D005307:Fertilization in Vitro; D006358:Hot Temperature; D009865:Oocytes / Q000166:cytology* / Q000378:metabolism*; D011247:Pregnancy; D013696:Temperature