The Effect of Human Follicular Fluid (FF) on Preimplantation Mouse Embryo Development in Vitro

  SUMMARY Since at oocyte retrieval for in vitro fertilization there is some FF become incorporate to egg, we decided to investigate the effect of this fluid on preimplantation embryo development in vitro. FF was obtained at the time of oocyte retrieval for IVF, centrifuged and then either inactivated by heat and stored at 4°c or without inactivation stored at-20°c until used. Late 2-cell embryos were collected from superovulated 8-weeks-old random-bred Swiss mice 48 after injection of hCG. Rates of development were compared between embryos cultured in Ham's F1O supplemented with 10% human albuminar serum (control group), heat-inactivated pure FF(HF1OO), Ham's FIO supplemented with 50%, 25% and 10% heat-inactivated FF(HF50, HF25, HF1O), non heat­inactivated pure FF(NF1OO) and Ham's PIO supplemented with 10% non heat-inactivated FF(NF1O). Between 150 to 500 embryos wert" cultured in each of these media. The percentages of embryos which reached blastocyst in HF1OO, HF50, HF25, HF1O and Ham's at 48h of culture were 58.6, 48.0, 37.6, 40.3 and 28.6 respectively which those in HF1OO and HF50 were significantly greater than those the others (P<0.05). After 72h of culture, these percentages were 86.1, 77.2, 75.0, 70.3 and 71 .6 respectively. In comparison only blastocyst­reached embryos in HF1OO was significantly greater than those in the rest (P<0.05). In contrast to HFs, almost all embryos which cultured in NF1OO degenerated and from those cultured in NF1O only 44.1 % reached blastocyst at 72hr of culture which was significantly lower than those in the other experimental groups (P<0.05). These results suggest that human heat-inactivated FF could support the mouse embryo development in vitro and accecerates and improves their growth in comparison with Ham's F1O+ serum while non beat-inactivated fluid retards embryo development.