Endocrynology of Embryoendometrial Interactions: A Hundred Years of Fascinating Discoveries; A. Psychoyos. Uterine Receptivity: Experimental Studies: Cell Biology of Endometrial Receptivity and of Trophoblast-Endometrial Interactions; H.W. Denker. Progesterone Directed Gene Expression in Rat Uterine Stromal Cells; J. Mulholland, et al. Uterine Receptivity: Clinical Studies: Receptive and Refractory Period in Human Implantation; J. Mandelbaum, et al. Characterization of the Human Endometrium in Relation to Implantation; P.C. Svalander, et al. The M.C. Chang Memorial Lecture: RU486: After Ten Years Novel Molecules and Reproductive Medicine; E.E. Baulieu. Pregnancy Recognition: Involvement of Local Mediators in Blastocyst Implantation; T.G. Kennedy. The Decidual Hormones and Their Role in Pregnancy Recognition; G. Gibori. Endometrial Responses to Receptivity: Embryo-Endometrial Interactions; S.K. Smith. Insulinlike Growth Factors and Their Binding Proteins in the Endometrium; L.J. Murphy. The Next Years: Future Prospect of Research on Endocrinology of Embryo-Endometrial Interactions; K. Yoshinaga. 21 additional articles. Index.

Long was I hugg'd close-long and long. Immense have been the preparations for me, Faithful and friendly the arms that have help'd me. Cycles ferried my cradle, rowing and rowing like friendly boatmen. For room to me stars kept aside in their own rings, They sent influences to look after what was to hold me. Before I was born out of my mother, generations guided me, My embryo has never been torpid, nothing could overlay it. -Walt Whitman, "Song of Myself" The womb is the seat of all mammalian life. In pregnancy, the uterus acquires this impor tance with the arrival of the fertilized egg, which takes up residence for periods ranging from about 2 weeks in the opossum to about 2 years in the elephant. The arrival of the embryo signals a crucial time for the establishment of pregnancy. For several days the blas tocyst remains free in the uterine lumen, where it depends on uterine secretions for its sur vival and differentiation. During this time, essential changes in the endometrium take place in preparation for attachment of the blastocyst and implantation. Early embryonic loss is an economic problem of global proportions in animal husbandry, where, in pigs and cattle for example, some 30% of all fertilizations fail to result in a pregnancy. In humans this figure may be even higher, and estimates of early spontaneous abortions range from 40 to 60% of all conceptions.

Early embryonic loss is a continuing social and economic global problem. In human populations the estimates of interruptions early in pregnancy range from 35-60%. In animal husbandry (swine, ruminants) fully 30% of pregnancies fail to survive early events of gestation. The futility associated with this persistant high risk is even more unsettling because of advances made in assisted reproductive technology which, although this very selective methodology has added to our knowledge of embryo-endometrial interactions, has resulted in a birth rate of only 14%. These studies have instigated comparisons of the live relative contributions of the embryo and the uterus to the outcome of pregnancy. These analyses have shown that we have learned significantly less about the role of the uterus in deciding the outcome of either natural or assisted pregnancies. In 1979 a quotation by George Corner was used to set the tone of a meeting that was devoted to discussion of the cellular and molecular aspects of implantation. In spite of the proliferation in research activity which occurred in the following 15 years our real understanding of the embryo transfer process has fallen short of our expectations. We use the Corner quotation, once again, to preface this symposium so that we may recall that the fundamental nature of the process which regulates embryo-endometrial interactions still escapes us.

The first edition of The Endometrium was a landmark publishing event in reproductive biology and medicine. Many important developments have occurred in the field, and this new edition has been substantially updated and expanded to include new topics with an improved format. With the addition of several new authors and topics, the Second Edition of The Endometrium has developed new coverage of transcriptomics, stem cells, genetics and in-utero programming. Other new areas strengthen to include: placentology in human and animal models, taking account of the tremendous current interest in the maternal-fetal interface and its role in pregnancy pathology, neonatal and adult health. The layout has also been improved in order to aid browsing and cross-referencing. This is an invaluable up-to-date innovative text that will appeal to a worldwide spectrum of academic and professional readers including postgraduate and postdoctoral researchers in reproductive biology. As well as trainees and health care professionals in obstetrics and gynecology and allied disciplines such as assisted reproduction and oncology. A panel of internationally respected authors has been carefully chosen for their insight, clear, fair writing style and scholarly perspective.