Ovarian hormonal function is under hypothalamo-hypophysis control during the genital life of women. Local hormonal production induces follicular stimulation and maturation. Two main types of functional disorder can be observed: unilocular cyst, related to an ovulation mechanism, and polycystic ovaries. The former is a follicular cyst related to the absence of LH stimulation, or a luteal cyst, which may be anechoic or display a heterogeneous content (pseudo-septa, pseudo-solid but avascular mass). The latter includes the polycystic ovarian syndrome, which is characterized by an increased ovarian area ( 6cm(2)), stroma and follicles number, the multifollicular ovaries, which are related to functional hypothalamic anovulation and characterized by a normal ovarian size with increased follicles number, and macropolycystic ovaries which are observed in case of previous pelvic infection disease or surgery. Functional disorders may be observed during pregnancy: luteoma, luteal cyst and hyperreactio luteinalis. Finally, ovarian insufficiency may occur too early.