Prolonged culture of human cryopreserved embryos with recombinant human leukemia inhibitory factor

Purpose: To evaluate the efficiency of recombinant human leukemia inhibitor y factor (LIF) in the prolonged culture of human cryopreserved-thawing embr yos. Methods: After thawing, all embryos were divided into four groups: (I) Huma n tubal fluid (HTF), (2) HTF + LIF; (3) M3(TH) medium, and (4) M3(TH) mediu m plus LIF: Following prolonged culture, embryo development in each group w as compared. Results: In embryo development from about the 2- to 4-cell to 9- to 16-cell stage, there were nonsignificant differences between each group. There was lower morula formation rate in group 1 (6.9%) than those in other groups ( 23.2%, 19.7%, 23.1%). The lower blastocyst formation in group 1 and 3 (0%, 0%) than those in group 2 and 4 (11.0%, 12.8%) were noted. Conclusions: LIF is beneficial for preimplantation embryos. LIF does not in fluence the early embryo development. LIF-supplemented HTF provided a simil ar culture environment for thawing embryos as LIF-supplemented M3(TH) mediu m.