These result in a decrease of the ovaries general supply of eggs that normally lasts until an average age of 51 for age of age-appropriate menopause.Genetic causes such as Turner syndrome have initial ovarian development but then ovaries degenerate rapidly during prenatal life, often leading to gonadal dysgenesis with streak ovaries. In those cases where POI is associated with adrenal autoimmunity, histological examination almost always confirms the presence of an autoimmune oophoritis in which follicles are infiltrated by lymphocytes, plasma cells, and macrophages that attack mainly steroid-producing cells and eventually result in follicular depletion.In some women FSH may bind to the FSH receptor site, but be inactive. By lowering the endogenous FSH levels with ethinylestradiol (EE) or with a GnRH-a the receptor sites are free and treatment with exogenous recombinant FSH activates the receptors and normal follicle growth and ovulation can occur. (Since the serum Anti-Müllerian hormone (AMH) level is correlated with the number of remaining primordial follicles some researchers believe the above two phenotypes can be distinguished by measuring serum AMH levels.Genetic associations include genetic disorders, autoimmune diseases, enzyme defects, and resistant ovaries.Mutations in FOXL2 cause Blepharophimosis Ptosis Epicanthus inversus Syndrome (BPES). Premature ovarian failure is part of the BPES Type I variant of the syndrome but not of the BPES Type II variant. DNA repair deficiency
BRCA1 protein plays an essential role in the repair of DNA double-strand breaks by homologous recombination. Women with a germline BRCA1 mutation tend to have premature menopause as evidenced by the final menorrhea appearing at a younger age.
Two to 5% of women with POI and a premutation in FMR1, a genetic abnormality, are at risk of having a child with fragile X syndrome, the most common cause of inherited intellectual disability.The diagnosis is based on ages less than 40, amenorrhea, and  elevated serum follicle-stimulating hormone (FSH) levels. Typical serum FSH levels in POI patients is in the post-menopausal range. Treatment will vary depending on the symptoms. It can include hormone replacement therapy, fertility management, and psychosocial support, as well as annual screenings of thyroid and adrenal function. Signs and symptoms
The signs and symptoms of POI can be seen as part of a continuum of changes leading to menopause. POI contrasts with age-appropriate menopause in the age of onset, degree of symptoms and sporadic return to normal ovarian function. As some women retain partial ovarian function, symptoms may not be as severe as regular menopause. In others, particularly with coexistent depression, symptoms such as decreased quality of life can be severe.Hormonally, POI is defined by abnormally low levels of estrogen and high levels of FSH, which demonstrate that the ovaries are no longer responding to circulating FSH by producing estrogen and developing fertile eggs. The ovaries will likely appear smaller than normal. The age of onset can be as early as 11 years. POI can be seen as part of a continuum of changes leading to menopause that differ from age-appropriate menopause in the age of onset, degree of symptoms, and sporadic return to normal ovarian function.