The development of one- and two-cell mouse embryos in the absence of human serum

One- and two-cell embryos were obtained from F1 hybrid female mice stimulated with human menopausal gonadotrophin and randomly distributed into two groups--group 1 (no serum) and group 2 (10% patient's serum). Fifty of 53 (94.3%) one-cell embryos in group 1 had cleaved to the blastocyst stage and 44 of 49 (89.79%) in group 2 after 96 hours (no significant difference--chi-square test). In the two-cell embryos in group 1, 78 of 89 (87.6%) reached the blastocyst stage after 72 hours and 80 of 86 (93.02%) in group 2 (no significant difference--chi-square test). According to microscopic evaluation cleavage to the blastocyst stage without serum supplementation is possible. The value of serum is discussed.