The effect of serum supplementation on the cleavage of human embryos.

The effect of serum supplementation was evaluated on 108 oocytes obtained from 29 patients. The oocytes were all mature and randomly distributed in two groups. Each ovum was paired with another ovum within the same patient. The experimental group contained no serum in the insemination and growth medium, but in the control group 10% serum was added to the insemination and growth medium. In the experimental group the cleavage rate was 66.7%, compared to 83.3% in the control group. The embryos from each patient were individually evaluated. The sign test was used for statistical analysis. A significant difference between the two groups (P = 0.01) indicated that in this study the addition of serum to the medium gives better cleavage results. The effect of serum on embryos is discussed, as well as the practical implications of this finding.