Oothecoma. The follicular oothecoma is formed as a result of a clump of a follicular liquid in a follicle; it is more often observed in the period of puberty and at young women. Represents thin-walled unicameral formation which diameter seldom exceeds 8 centimeters. In process of augmentation of a cyst the cells covering an internal surface of its wall, will atrophy. Small follicular cysts, possess the moderate hormonal activity. Follicular cysts in diameter up to 4-6 centimeters clinically often are not shown. At diameter of a follicular cyst of 8 centimeters and more there can be a torsion of a leg of the cyst, accompanied disturbance of a circulation and a necrosis of a tissue of an ovary and break of a cyst. In these cases the picture of an acute abdomen develops.