Sperm cells evolved to acquire a sophisticated motility structure called a
flagellum which gives spermatozoa a self-propelling force. Nonetheless, in internal
fertilizing species such as mammals, the length and complexity of the female genital
tract mean that sperm motility is insufficient to accomplish the sperm’s mission of
transferring genetic material to the oocyte. Thus, a long-standing question in the
reproductive biology field has been how spermatozoa are delivered to the oocyte
surface. Several mechanisms have been proposed to help sperm transport, such as
oviduct peristalsis, chemotaxis, thermotaxis and rheotaxis. In this chapter we will
discuss the state of the art of sperm chemotaxis.
Keywords: Chemoattractants, Chemoattractant sources, Methods for chemotaxis
evaluation, Sperm chemotaxis.
