title: Aseptic vitrification of blastocysts from infertile patients, egg donors and after IVM.
abstract: During embryo vitrification, it is advisable that cooling and storage should occur in a carrier device in which there is complete separation of the embryos from liquid nitrogen to ensure asepsis. The consequence of a reduction in the cooling rate resulting from the heat-insulating barrier aseptic devices has to be counteracted by gradually increasing intracellular concentrations of cryoprotectants without inducing a toxic effect. Blastocysts originating from couples with male and/or female factor infertility (group 1) or from oocyte donors (group 2) or from in-vitro matured oocytes (group 3) were gradually exposed to increasing concentrations of dimethylsulphoxide/ethylene glycol (5/5%, 10/10% and 20/20%) before aseptic vitrification using a specially designed carrier (VitriSafe), a modification of the open hemi-straw plug device. A total of 120 aseptic vitrification/warming cycles were performed in group 1, 91 in group 2 and 22 in group 3. Survival rates before embryo transfer, ongoing pregnancy and implantation rates were as follows: for group 1, 73, 43 and 26%; for group 2, 88, 53 and 34%; and for group 3, 69, 50 and 38%, respectively. In spite of reduced cooling rates due to aseptic vitrification conditions, a three-step exposure to cryoprotectant solutions protects the embryos effectively from cryo-injuries and guaranties high survival rates.
authors.affiliation: IVF Centers Prof. Zech, Bregenz, Austria. pierrevdz@hotmail.com
authors.forename: P
authors.initials: P
authors.lastname: Vanderzwalmen
authors.forename: F
authors.initials: F
authors.lastname: Ectors
authors.forename: L
authors.initials: L
authors.lastname: Grobet
authors.forename: Y
authors.initials: Y
authors.lastname: Prapas
authors.forename: Y
authors.initials: Y
authors.lastname: Panagiotidis
authors.forename: S
authors.initials: S
authors.lastname: Vanderzwalmen
authors.forename: A
authors.initials: A
authors.lastname: Stecher
authors.forename: P
authors.initials: P
authors.lastname: Frias
authors.forename: J
authors.initials: J
authors.lastname: Liebermann
authors.forename: N H
authors.initials: NH
authors.lastname: Zech
mesh_terms: D001755:Blastocyst / Q000166:cytology* / Q000187:drug effects; D015925:Cryopreservation; D003451:Cryoprotective Agents / Q000494:pharmacology; D046149:Embryo Culture Techniques / Q000295:instrumentation; D010064:Embryo Implantation; D004624:Embryo Transfer; D005260:Female; D006801:Humans; D007247:Infertility, Female; D008297:Male; D011247:Pregnancy; D018873:Pregnancy Rate; D014019:Tissue Donors
chemical_list: D003451:Cryoprotective Agents