Improved fertilization rates of human oocytes in coculture

Passaged human tubal ampullary epithelial cells from cell lines were used to evaluate fertilization rates and the support of early human embryonic cleavage in vitro. A total of 225 mature oocytes from 32 patients was used in this study. Oocytes from each patient were equally allotted at random to two groups. One hundred thirty-two oocytes were inseminated in the presence of passaged human ampullary cells, while 123 oocytes were inseminated in culture medium alone. Fertilized oocytes were transferred to tubal ampullary cell monolayers and monitored for up to 48 hr. Eighty-five percent of oocytes fertilized in coculture, as compared to 67% in medium alone (P less than 0.01). A higher percentage of good-quality embryos was observed in cocultures than in controls (79 vs 67%; P less than 0.05). Binding of sperm to ampullary monolayer cells was observed. Human ampullary-cell cocultures may be useful to improve fertilization rates and embryonic viability and thus increase take-home baby rates for in vitro fertilization programs.