The effect of x-irradiation on the implantation and development of the white rat fetus

X-ray whole body irradiation (200R, exposure dose) was performed on young virgin females of about 4 months old. The female rats, divided into three groups, were treated as follows: Female rats as control (unirradiated = 1Kt): female rats irradiated before mating (RSbK), and female rats irradiated after mating (RSsK). The average number of surviving foetuses at 20 days gestational stage of 1Kt was compared with that of RSbK, and no significant difference was found (P<=0.05) while the difference between the average number of RSsK foetuses compared with that of 1Kt and RSbK was highly significant (P<0.01). A decrease in the average number of surviving foetuses was found in RSsK, although the analysis of variance of all groups, revealed no significant difference (P<=0.05) in the average number of implantations and weight of the foetuses. (author)