Correlation analysis of human embryo Le^Y glycan antigen expression and embryo quality

This study assessed the feasibility of using Le^Y glycan secretion level in human embryos as a method of judging embryo quality. Embryo culture media from patients receiving in vitro fertilization-embryo transfer was collected, and quality scores of embryos were recorded. Secretions of Le^Y in the culture media in different development stages (from 4-cell to 10-cell), embryos in the same development stage of the same patients (8-cell/I) and embryos in the same development stage of different patients (8-cell/I) were examined by dot-blot. Embryos were divided into a hypersecretion group and hyposecretion group, based on their Le^Y secretion level. The embryo quality was evaluated by clinical observations, the number which developed to D3 cell stage and the number of successful embryo transplantations. Le^Y secretion increased as embryos developed from 4-cell to 10-cell (P<0.05); secretion of Le^Y of 8/I is not identical; development speed of embryos with different secretion level of Le^Y was also different. The number of embryos which developed to 6-cell or higher was 82.2% in the Le^Y hypersecretion group but only 60% in the hyposecretion group. The rate of successful transplantation was significantly higher in the hypersecretion group (71.1 vs. 40%). In conclusion, Le^Y glycan secretion level in human embryos is closely related to embryo quality. Le^Y may become a useful measure to evaluate embryo quality in the future.