[Role of Fallopian tube in fertilization]

Fallopian tubes are complex organ where fertilization occurs after inverse migration of spermatozoa and oocyte. However, tube cannot be restricted to be fertilization site. The different tubal segments represent specific microenvironments to favour capacitation and fertilization process and to support early embryonic development. Tubal physiology permits tubal transport of gametes and embryon on adequate time by variations of smooth muscles contractility among tubal segments and during menstrual cycle. Tubes should control the number of competent spermatozoa present on fertilization site. Composition and viscosity of tubal fluid also vary along the tube and during cycle. Specific components of tubal fluid such as HuOGP interfere with gamete maturation, fertilization process and early embryonic development. Alteration of part of these functions could explain some tubal infertilities leading with normal tube morphology.