Ejaculated sperm enter COCs more rapidly than epididymal sperm.

Data are presented as ejaculated/epididymal sperm (ratio). The adjusted ratio is the ratios of ejaculated/epididymal sperm in the COC standardized to the ratios of ejaculated/epididymal sperm in the COC-free control preparation in the same dish. Ejaculated sperm enter COCs more rapidly than epididymal sperm.