Analysis of the clinical outcomes of human embryo transplantation after frozen-thawing protocol:120 cycles

Objective To investigate the outcomes of embryonic transplantation after cryopreservation and thawing.Methods A slow-freezing and rapid-thawing protocol was used in human embryos at 2~4cells stage.The clinical outcomes after transfer of the frozen/thawed embryos in 120 cycles were analysed.Eighty-eight patients accepted 120 cycles of frozen /thawed embryo transfer in the First Affiliated Hospital of Harbin Medical University from January 2003 to May 2007.Results A total of 370 embryos were thawed,of which 316 embryos survived and 232 embryos survived intactly.Three hundred and sixteen embryos were transferred.The clinical pregnancy rate was 32.5%(39/120) and the implantation rate was 16.5%(52/316).There was no significant difference in age,serum estrogen levels,endometrium thickness,survival rates of frozen/thawed embryos and intact survival rates between pregnancy group and non-pregnancy one(P0.05).However,the good-quality embryos ratio was significantly higher in the pregnancy group than that in non-pregnancy one(P0.01).Conclusion The quality of embryo has a significant effect on the clinical pregnancy rate after transfer of frozen/thawed embryos.Accumulative pregnancy rate in IVF protocol may increase utilizing transplantation of frozen/thawed embryos.