title: The impact of two different thaw protocols on outcomes of vitrified cleavage-stage embryos transfer.
abstract: The objective of this study was to evaluate the gestational results obtained with vitrified-thawed human cleavage-stage embryo by two different thaw protocols. Embryo development was observed to cleavage-stage and embryos were cryopreserved by vitrification on day 3 after oocyte retrieval. 51 cycles were thawed using vitrification warming kit with decreasing concentrations of sucrose in 3 dilutions ( 1.0, 0.5 and 0 mol per L respectively) as group 1, 56 cycles were thawed with decreasing concentrations of sucrose in 5 dilutions ( 0.8, 0.6, 0.33, 0.2 and 0 mol per L respectively) as group 2. Embryo survival (> 50 percent intact blastomeres), complete embryo survival (100 percent intact blastomeres), pregnancy and implantation rates were compared, and development rates the day after thawing were also compared. Multivariate analysis showed a significant difference in embryo immediate morphological survival rate, complete survival and clinical pregnancies rate between the two groups respectively (87.0 vs. 98.6 percent, p=0.000; 71.0 vs 82.0 percent embryo subsequent development rates, mean number of transferred embryos was similar between the two groups. (61.4 vs. 61.3 percent, p=0.502; 2.2 +/ 0.5 vs. 2.4 +/- 0.6, p=0.113). In addition, no differences in implantation rate were observed between two groups (17.7 vs. 25.6 percent, P=0.138). No difference in the multiple pregnancy rates was found among the two groups also.
authors.affiliation: Department of Assisted Reproductive Medical Center, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, 32 Yi Huan Lu Xi Er Duan, Chengdu, Sichuan, China. xiaojian.z@gmail.com
authors.forename: Xiao-jian
authors.initials: XJ
authors.lastname: Zhang
authors.forename: Ye-Zhou
authors.initials: YZ
authors.lastname: Yang
authors.forename: Qun
authors.initials: Q
authors.lastname: Lv
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Xue-hua
authors.initials: XH
authors.lastname: Cao
authors.forename: Xiao-jie
authors.initials: XJ
authors.lastname: Li
authors.forename: Mei-xu
authors.initials: MX
authors.lastname: Liao
authors.forename: Chun
authors.initials: C
authors.lastname: Guo
mesh_terms: D000328:Adult; D001757:Blastomeres / Q000502:physiology*; D002970:Cleavage Stage, Ovum / Q000502:physiology*; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000378:metabolism*; D010064:Embryo Implantation; D004624:Embryo Transfer / Q000379:methods*; D005260:Female; D005615:Freezing; D006801:Humans; D008297:Male; D011247:Pregnancy; D018873:Pregnancy Rate; D013395:Sucrose / Q000378:metabolism*; D058989:Vitrification
chemical_list: D003451:Cryoprotective Agents; D013395:Sucrose