Evaluation of media, protein supplements and potassium concentration for human in vitro fertilization and embryo transfer by preimplanted mouse embryo development.

A two-cell mouse embryo was used to investigate the effect of three different media and protein supplements together with different potassium (K+) concentrations on embryo development. The embryos of the ICR mouse showed higher expanded blastocyst rates in Biggers-Whitten- Whittingham (BWW) than in Ham's F10 (F10) and Whittingham's T6 (T6). The embryos of the C57BL X CBA strain showed the highest hatching rate in BWW but the expanded blastocyst rate was highest in F10. Embryos from both strains developed more rapidly with BSA supplement with no difference between human serum (HS) and fetal cord serum (FCS). Relatively higher K+ concentrations (7.7 mM and 17.8 mM) suppressed 2-cell mouse embryo development. F10 and BWW were used for human in vitro fertilization and embryo transfer (IVF-ET). The fertilization rate was significantly higher in BWW than in F10. Two viable pregnancies were obtained in BWW cycles. This study supports the use of BWW over other standard media for human IVF-ET.