One hundered and twenty adult female albino rats were divided intofour groups to study the pathologic change which induced due to longadministration of high and Iow dose of sex hormones (estrogen,progesterone and their combination).Experimental groups were treated as follows:Group (gp.) I: (subgp. A and B) subcutaneous injected with 0.1 mgand 0.05/rat of estrogen respectively and (subgp. C and D) orally received0.1 mg and 0.05 mg per rat of estrogen respectively.Group 1/: (subgp. A and B) orally received 2.5 mg and 1.5 mg/rat ofprogesterone respectively.Group /11: (subgp. A and B) orally received combination of (0.1 mgestrogen + 2.5 mg progesterone) and (0.05 mg estrogen + 1.5 mg progesterone )/rat respectively.Group IV: served as untreated controls.The administration of above mentioned drugs to the animals were continued six days weekly until the time of death or sacrificed (16, 24 and 36 weeks).Clinical signs and pathological findings were recorded: Group (1)which received estrogen alone showed emaciation, decrease in body weightin most rats beside loss of hair particularly on the pelvic region in rats of subgp, (A,B). The uterus in most rats was slightly enlarged and contained 2- 3 ml of serous fluid. It was measured (2-3 times of its normal size with