Sperm interaction with the female reproductive tract.

Sperm transit in the female tract is a critical event for the success of fertilization. From their deposition in the vagina to final migration in the oviduct, sperm pass through the different compartments of the genital tract in which they encounter different environments. The cervix and the uterotubal junction (UTJ) are two barriers with different relative importance according to the species. The protein composition, the degree of glycosylation and the hydration of the cervical mucus change during the oestrous cycle. Several sperm surface proteins are associated with their migration through the cervical mucus and the UTJ. Data regarding the interaction of sperm with secretions of the epithelial tissue lining the different compartments of the female genital tract during the sperm transit are reviewed, with a particular emphasis on the migration of sperm through the cervix.