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Polycystic ovary syndrome

  • Definition

    Polycystic ovary syndrome is a condition in which there is an imbalance of a woman's female sex hormones. This hormone imbalance may cause changes in the menstrual cycle, skin changes, small cysts in the ovaries, trouble getting pregnant, and other problems.


    Alternative Names

    Polycystic ovaries; Polycystic ovary disease; Stein-Leventhal syndrome; Polyfollicular ovarian disease


    Causes, incidence, and risk factors

    Female sex hormones include estrogen and progesterone, as well as hormones called androgens. Androgens, often called "male hormones," are also present in women, but in different amounts.

    Hormones help regulate the normal development of eggs in the ovaries during each menstrual cycle. Polycystic ovary syndrome is related to an imbalance in these female sex hormones. Too much androgen hormone is made, along with changes in other hormone levels.

    It is not completely understood why or how the changes in the hormone levels occur.

    Follicles are sacs within the ovaries that contain eggs. Normally, one or more eggs are released during each menstrual cycle. This is called ovulation. In polycystic ovary syndrome, the eggs in these follicles do not mature and are not released from the ovaries. Instead, they can form very small cysts in the ovary.

    These changes can contribute to infertility. The other symptoms of this disorder are due to the hormone imbalances.

    Women are usually diagnosed when in their 20s or 30s, but polycystic ovary syndrome may also affect teenage girls. The symptoms often begin when a girl's periods start. Women with this disorder often have a mother or sister who has symptoms similar to those of polycystic ovary syndrome.