1 Embryology Section, Division of Experimental Chemotherapy, Sloan-Kettering Institute for Cancer Research, Memorial Center for Cancer and Allied Diseases
Five alkylating agents and x-rays, administered to pregnant rats on the twelfth day of gestation and which were killed on the twenty-first day, produced malformations in the fetuses.
The dosages producing four measured effects on the pregnant rats and their fetuses for each of the five alkylating agents and x-rays were found to resemble each other more than in a comparison of six antimetabolites in a previous study.
There is a similarity of the malformations produced by these agents, but some distinct differences in gross soft-tissue and skeletal abnormalities are described.