Spermatozoal migration and lymphatics: a hypothesis.

The exact mechanism of sperm migration is still unknown. Lymphatics may act as transporting channels for the migration of sperms. The relevant literature is reviewed and it is suggested that myometrial contractions may allow the lymphatics of the uterus to take up the sperms and pump them actively towards the uterine tubes, where they are pumped again by tubal contractions towards their destination at the end of the tube where they fertilize the ovum.