A Reproductive Lexicon


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Anovulation is the absence of ovulation, or oocyte release from the ovary, in the menstrual cycle. Anovulation may be physiological before puberty, during pregnancy and lactation, or after menopause. It may also be pathological due to disorders affecting the ovaries, pituitary gland, or hypothalamus. Chronic anovulation accounts for about 30% of all cases of female infertility. The most common cause of chronic anovulation is polycystic ovarian syndrome (PCOS).