Physiology of Prematurity.

This is the first of a series of conferences to explore problems associated with premature birth. The first section of the book is devoted to the general topic of fetal-maternal endocrinology in late pregnancy. The large size of the adrenal in the fetus led to considerable speculation as to its physiological significance. Does chorionic gonadotropin stimulate the fetal cortex early in gestation? Does the small adrenal of the anencephalic monster indicate a failure of pituitary corticotropin in the last trimester? What is the relative responsiveness of the newborn adrenal to corticotropin? Is hypoxia a stimulus for adrenal enlargement? Does adrenal growth decline with a shift from fetal to adult hemoglobin? Androgens can be extracted from fetal adrenal tissue, but whether they are released into the fetal circulation is not known. The defective steroid biosynthesis giving rise to the adrenogenital syndrome was mentioned. There were then some comments on uterine contraction