Effect of Anti-Placenta Serum on Development of Foetus in the Pregnant Rat

Abstract

(1) Rabbit-anti-rat-placenta serum effectively interferes with the normal development of the placenta and foetus in the pregnant rat. (2) The same result is obtained with much smaller injections of rabbit anti-rat-whole-blood serum. (3) Rabbit anti-rat-serum serum fails to influence pregnancy unless injected in sufficient volume to induce anemia. (4) Anti-hormone serum and normal rabbit serum are without effect on pregnancy in the rat. (5) The immunological factor or factors responsible for the resorption of the foetuses following the injection of anti-placental serum and anti-whole-blood serum are as yet unknown.