STUDIES ON THE ROLE OF GROWTH HORMONE IN PREGNANCY1

Abstract
IT HAS been postulated by various workers that growth hormone might play a part in gestation in view of the rapid fetal growth and marked nitrogen retention. Attempts to detect this hormone in the urine of pregnant women and blood of pregnant goats have met with failure. (Cotes and Young, 1951.) Results obtained in our laboratory (G. Beaton et al., 1954) have shown that there is a sudden increase in fetal growth and a simultaneous appearance of certain biochemical changes at the 15th day of pregnancy in the rat. These changes include haemodilution, lowered rate of urea formation by liver slices, lowered liver alanine-glutamic transaminase activity, increased liver weight and changes in carcass composition. The sudden simultaneous appearance of these alterations suggested the action of a hormone factor. A previous study (G. Beaton et al., 1953), in which purified growth hormone was administered to normal rats indicated similar enzymic changes.