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Poor ovarian reserve: (also known as impaired ovarian reserve, premature ovarian aging or declining ovarian reserve) is a condition of low fertility characterized by 1): low numbers of remaining oocytes in the ovaries or 2) possibly impaired preantral oocyte development or recruitment. Recent research suggests that premature ovarian aging and premature ovarian failure (aka primary ovarian insufficiency) may represent a continuum of premature ovarian senescence. It is usually accompanied by high FSH (follicle stimulating hormone) levels. Quality of the eggs (oocytes) may also be impaired as a 1989 study by Scott et al. of 758 in vitro fertilisation (IVF) cycles showed a dramatic decline in implantation rates between high (> 25 mIU/mL) and low day three FSH (<15 mIU/mL) women even though the ages of the women were equivalent between the two groups (mean age 35 years). However, other studies show no association with elevated FSH levels and genetic quality of embryos after adjusting for age. The decline in quality was age related, not FSH related as the younger women with high day three FSH levels had higher live birth rates than the older women with high FSH. There was no significant difference in genetic embryo quality between same aged women regardless of FSH levels. A 2008 study concluded that diminished reserve did not affect the quality of oocytes and any reduction in quality in diminished reserve women was age related. One expert concluded: in young women with poor reserve when eggs are obtained they have near normal rates of implantation and pregnancy rates, but they are at high risk for IVF cancellation; if eggs are obtained, pregnancy rates are typically better than in older woman with normal reserve. However, if the FSH level is extremely elevated these conclusions are likely not applicable. ==Etiology== * Natural decline of ovarian reserve due to age. * Idiopathic. * Genetic factors, such as fragile x syndrome. Approximately 20–28% of women with an FMR1 premutation (55–200 CGG repeats) experience fragile x primary ovarian insufficiency (POI) and another 23% experience early menopause (i.e., menopause before the age of forty five).〔(The National Fragile X Foundation )〕 * Autoimmune disorders. * Adrenal gland impairment. * Iatrogenic, e.g., due to radiation, chemotherapy or surgery, such as laserization of the surface of the ovary to treat endometriosis. Excessive laparoscopic ovarian drilling has been reported to cause premature ovarian failure. (The primordial follicles are located in the thin outer one-millimeter layer of the ovary.) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Poor ovarian reserve」の詳細全文を読む スポンサード リンク
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