Robert M. Colver

SUCCESS RATES FOLLOWING INTRACYTOPLASMIC SPERM INJECTION ARE IMPROVED BY USING ZIFT VS. IVF FOR EMBRYO TRANSFER

AbstractPurpose: The purpose of this study was to analyze whether the mode of embryo transfer (ZIFT vs IVF) affected the outcome in intracytoplasmic sperm injection (ICSI) cycles. Methods and Results: Eighty-two ICSI cycles (42 ZIFT and 40 IVF) were analyzed. Several variables, including patient age and weight, numbers of mature eggs collected, injected, and fertilized, fertilization rate, number of fertilized eggs obtained per cycle, numbers of zygotes/embryos transferred, clinical pregnancy rate, and implantation rate, were compared. Mean patient age and weight were identical. The mean number of mature eggs collected and injected and fertilization rate were significantly higher in the ZIFT group, however, the mean numbers of zygotes/embryos transferred were identical. The clinical pregnancy and implantation rates in ZIFT cycles (52.3 and 23.2% respectively) were significantly higher than in IVF cycles (17.5 and 9.7%). Conclusions: These data suggest that ZIFT is the more appropriate method for transfer of ICSI-derived embryos.

Influence of growth factors in defined culture medium on in vitro development of mouse embryos**Supported by a Biomedical Research Support grant from the Medical College of Georgia.

Two-cell mouse embryos were cultured in Hams F-10 medium (Gibco, Grand Island, NY) supplemented with various concentrations of transferrin, insulin, epidermal growth factor, platelet-derived growth factor, or fibroblast growth factor. Rates of development and the cell numbers per blastocyst were compared between embryos cultured in Hams F-10 alone versus growth factor (GF) supplemented media. Rates of development in the presence of GF were inhibited significantly in some cases, and the cell numbers per blastocyst were identical in all groups. When compared with in vivo derived blastocysts, however, all in vitro cultured embryos had significantly less cells per embryo. These results suggest that GF supplementation of media for culture of early preimplantation embryos does not stimulate the rate of embryonic development in vitro.