Uterine Grafts

Abstract

(1) Foetal tissues were transplanted into the pseudo-pregnant uterus of the rabbit, a suitable position for such grafts owing to the raised nutrition of the uterus occurring in the early stages of pseudo-pregnancy. (2) Several tissues particularly large amounts of cartilage and small quantities of epithelial tissue persisted and grew, the former undergoing ossification. (3) The growth of these foetal tissues in the pseudo-pregnant uterus did not cause the corpus luteum of pseudo-pregnancy to persist or the mammary gland to thicken as in pregnancy. (4) Since--(a) the foetal tissues only grew where they were attached to the muscle layer of the uterus, although every effort was made to attach them to the mucosa; (b) the parts of the grafts lying in connection with the mucosa were absorbed rather than nourished; and (c) the introduction of living foetal tissue failed to cause any further development of the deciduomata which were produced by cutting the pseudo-pregnant mucosa--it is suggested that normally the attachment of the foetus is caused by the active erosive (digestive) agency of the foetal trophoblast, a function which is absent in the cells of the foetus itself. (5) It seems probable that just as the small deciduomata are formed as a response to a cut so the large maternal placenta is formed as a response to the continuous erosion by the foetal trophoblast.