Influence of STH and Cortisone on Foetal Growth 169 



Conversely, the offspring of the control mother suckled by 

 the rat treated with cortisone during gestation, are retarded 

 in growth and show dorsal alopecia as well as markedly 

 delayed sexual development. Although in both cases the milk 

 intake of the newborn appears to be normal, the result of the 



Controls 



Cortisone 



Fig. 7. Growth curves of young rats born of mothers treated 

 with cortisone during pregnancy. 



exchange of mothers indicates that cortisone has an unfavour- 

 able effect on lactation. 



The results on two sets of animals obtained at a six months 

 interval prove this. The rats in the first set received 20 mg. of 

 cortisone for 5 days following parturition and 10 mg. after 

 this; those in the second set received 20 mg. of cortisone for 

 15 days following parturition. The cortisone treatment of the 



