To study the effect of cadmium on fetus and placenta of pregnant rat, 33 pregnant rats of Sprague-Dawley strain were used in this experiment (One control group and four treated groups as A, B, C, D).
Group A was administered per os 50mg of Cd/4ml/kg/day once a day for two days on 4th and 5th gestational days, Group B on 8th and 9th days, Group C on 12th and 13th days, and Group D on 16th and 17th days.
Before cadmium administration, body weight of each rat in all groups was measured. The results obtained were as follows;
1. There had been a significant decrease in the body weights of cadmium treated groups for 3,4 days after administration. The rate of body weight gain slowly increased, but still lower than that of the control group. But their body weight on the 20th day of pregnancy were remarkably less than that of control group (p<0.05).
2. The number of absorbed or dead fetuses was increased, as the cadmium was administered in the later gestational days. But the weights of fetuses and litter size were decreased.
3. The cadmium level of placenta in group A was 0.10pg/g, in group B 0.49ug/g, in
group C 1.O7,ug/g, in group D 5, o6,ug/g, and in control group 0. lOpg/g.
4. The cadmium concentration of the fetuses in control group was not detectable but that
in group A was 0.04,ug/g, in group B 0.35,ug/g, in group C 0.27ag/g, and in group D
0.44lig/g.
5. Histopathological examination also showed that necrosis of trophoblast, congestion,
hemorrhage and disorganization of maternal blood vessels were apparent due to cadmium
toxicity. As the days of gestation went on, histopathological changes got severer.
These results indicate that cadmium contents in treated groups caused the adverse effects
on placenta.
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