Egg transport in the fallopian tube.

The transport of eggs from the site of ovulation to the site of implantation is a fundamental step of the reproductive process in the female. The fallopian tube effects the major part of this function and times the passage of eggs into the endometrial environment. As a result of different combinations of speed of progression and retention periods through the various regions of the oviduct, the pattern of transport differs from one species to another. The role of muscular contraction, ciliary movement and flow of secretions in the mechanisms of progression and retention are still poorly understood. Estrogens and progestins have a pronounced influence upon egg transport, but the responses to exogenous hormones are quite variable and depend mainly upon species, dose and time of administration. Species differences prevent from broader generalizations at this time and indicate the need for further comparative studies.