The role of the oviduct in reproduction; our knowledge and our ignorance

Abstract

Processes essential to reproduction known to occur in the oviducts of Eutherian mammals include sperm transport, capacitation, ovum pick-up and transport, fertilization and embryo transport and nourishment. Our knowledge of these processes in our own species, man, is incomplete. The reasons underlying our lack of information concerning the physiology of the human Fallopian tube are ethical, philosophical, and technical. Although some of our failure to obtain definitive data in women has been due to ethical constraints we have also been limited philosophically by our inability to formulate the critical questions, and pragmatically by the lack of technology with which to accurately measure many biological phenomena. After more than a half century of clinical interest in female infertility, we are unable to assess accurately a single physiological function of the Fallopian tube. Our clinical armamentarium is limited to appraisals of the patency of the tube to gas or liquid, and to examination of the external appearance and texture of the tube. Even if all ethical constraints were removed, it would still be necessary to identify the important questions, design the critical experiments, and to develop the required technology.In this essay we shall emphasize postovulatory events, specifically fertilization, ovum pick¬ up, and ovum and embryo transport. We will discuss the pertinent physiological phenomena, and then we shall attempt to correlate tubai anatomy and physiology with clinical considerations.

Oviductal secretion and gamete interaction

“…Until a few decades ago, the oviduct was considered as a simple passive conduit that provided an optimal microenvironment in terms of temperature, pH, osmotic pressure, nutrients, and oxygen pressure, enabling both R8 S Ghersevich and others the fertilization process and the early stages of embryo development (Pauerstein & Eddy 1979). The accumulated experimental evidence reviewed in the present work supports that the oviduct is actively involved in the reproductive process, considering that its secretion contains molecules capable of modulating gamete functions and interaction.…”

Partial tubal salvage through neosalpingostomy in a 12-year-old girl with combined ovarian and fallopian tube torsion

“…The fallopian tube appears to readily adapt to anatomical changes and restrictions [17]. It has been shown that even removal of segments of ampulla or the ampullary-isthmic junction in rabbits does not prevent fertility [19].…”

Tubal Microsurgery

“…Fertility is unaltered after resection of the utero-isthmic junction or the ampullary-isth mic junction [8][9][10][11], which demonstrates that no essential sphincters exist on these sites. The isthmus itself appears to be re sponsible for the transistory retardation in ovum transport.…”