Materials and Methods: n-hexane, ethyl acetate, ethanol extracts of soya plant were administered to the rats by oral route at 100 and 200 mg/kg doses (SID) for 1 month. By monitoring the menstrual cycle with vaginal smear method, diestrus stage of the rats were determined. At the end of experimental period the animals were euthanized. Genital system organs taken of rats were analyzed by stereological methods. Follicules were counted with optical dissector method in the ovaryum stereologically, the weights of the ovaries, uterus were also evaluated.

Results: Some changes occured in genital system of the rats which were given at 200 mg/kg dose of soy ethanol extract. In test groups vaginal aperture increased, uterine appeared likehyperemia while significant weight increase did not occur. The weight of relative ovarium, uterus weight increased, coarsening of epithelial cells was observed. No significant difference was observed in all groups regarding the numbers of primordial, primary follicles. Diameter of secondaryfollicule reduced while the number of secondary follicule increased in 200 mg/kg ethanol extract administered group, when compared to control group. The amount of isoflavone content was determined by using high pressure liquid chromatography technique on the active extract. The amount of daidzein, genistein were found to be 3.851 μg/gand 3.127 μg/g, respectively in the ethanol extract.

Conclusion: It could be stated that phytoestrogens in soya plant dose-dependently affect the female genital system.