IONIZING RADIATIONS: EFFECTS ON EMBRYO, FETUS 



TABLE II 



Anomalies Reported Following Himan Fetal X-Irradiation ^ 



13 



1. Microcephaly (most frequent) 



2. Hydrocephalus 



3. Poroncephaly 



4. Mental deficiency 



5. Mongolian 



6. Idiocy 



7. Head ossification defects 



8. Skull malformations 



9. Micromelia 



10. Microphthalmus 



11. Microcornea 



12. Coloboma 



13. Strabismus 



14. Cataract 



15. Chorioretinitis 



■'' This table lists thirty coiigcnital anomalies found in humans following fetal .\-ii radiation. .Vote that 

 the most frequent type of anomaly relates to the central nervous system. Most, if not all of these 

 anomalies, have been produced in experimental animals by exposure during embryonic development. 



'' It must be remembered that the levels of irradiation which are hazardous for the embryo or fetus 

 aie very much lower than those foi the somatic tissues of the adult organism. It is, therefore, obvious 

 that extreme caution should be exerted where either the reproductive organs or the developing embryo 

 might be involved. We do not yet know the extent or the duration of radiation effects on the fetus or 

 the germ cells. 



TABLE III 



Effect of Low-Dose X-ravs on the Early 

 MorsE Embryo ' '' 



^ 



Controls 



5 r at 1 .5 dav 



630 



80 



» This table presents data following 5 r exposure of the mou.se embryo at !'/> days post conception. At 

 this time, the mouse embryo is in the 2 cell stage. Eighty such embryos exposed to 5 r gave 15% 

 resorptions which was almost a W7( increase over the expected 5.70^ of the controls. No exencephaly 

 appeared. 



*> .\n inciease of ').W, in intrauterine deaths caused by 5 r exposure at 1-2 cell stage. 



