Premature Ovarian Failure (POF), also known as primary ovarian insufficiency, is the loss of function of the ovaries before age 40.[1] A commonly cited triad for the diagnosis is amenorrhea, hypergonadotropinism, and hypoestrogenism.
Incidence/prevalence
It has been estimated that POF affects 1% of the population.[2] It affects approximately 1-4% of the female population in the U.S., which is about 150,000.citation needed
Presentation
Normally, ovaries supply women with eggs until about age 51, the average age of natural menopause.
POF is not the same as a natural menopause, in that the dysfunction of the ovaries, loss of eggs, or removal of the ovaries at a young age is not a natural physiological occurrence.
Infertility is the result of this condition, and is the most discussed problem resulting from it, but there are additional health implications of the problem, and studies are ongoing. For example, osteoporosis or decreased bone density affects almost all women with POF due to an insufficiency of estrogen. There is also an increased risk of heart disease, hypothyroidism in the form of Hashimoto's thyroiditis, Addison's disease, and other auto-immune disorders.
Hormonally, POF 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 shriveled.
Age of onset can be as early as the teenage years but varies widely. If a girl never begins menstruation, it is called primary ovarian failure. The age of 40 was chosen as the cut-off point for a diagnosis of POF. This age was chosen somewhat arbitrarily, as all women's ovaries decline in function over time, however an age needed to be chosen to distinguish usual menopause from the abnormal state of premature menopause. Premature ovarian failure however often has components to it that distinguish it from normal menopause.
By the age of 40, approximately one percent of women have POF.[3] Women suffering from POF usually experience menopausal symptoms, which are generally more severe than the symptoms found in older menopausal women.
Causes
The cause of POF is usually idiopathic. Some cases of POF are attributed to autoimmune disorders, others to genetic disorders such as Turner syndrome and Fragile X syndrome. In many cases, the cause cannot be determined. Chemotherapy and radiation treatments for cancer can sometimes cause ovarian failure. In natural menopause, the ovaries usually continue to produce low levels of hormones, but in chemotherapy or radiation-induced POF, the ovaries will often cease all functioning and hormone levels will be similar to those of a woman whose ovaries have been removed. Women who have had their tubes tied, or who have had hysterectomies, tend to go through menopause several years earlier than average, likely due to decreased blood flow to the ovaries. Family history and ovarian or other pelvic surgery earlier in life are also implicated as risk factors for POF.
The POF Fact Sheet lists potential causes of POF:
English: http://www.pofsupport.org/information/factsheet/fact_sheet_english.pdf
Laboratory
Serum follicle-stimulating hormone (FSH) measurement along can be used to diagnose the disease. Two FSH measurements with one-month interval have been a common practice. The anterior pituitary secretes FSH and LH at high levels due to the dysfunction of the ovaries and consequent low estrogen levels. Typical FSH in POF patients is over 40 mlU/ml (post-menopausal range).
Fertility
Between 5 and 10 percent of women with POF may spontaneously become pregnant. Currently no fertility treatment has been found to effectively increase fertility in women with POF, and the use of donor eggs with In-Vitro Fertilization (IVF) and adoption have become more popular as a means of becoming parents for women with POF. Some women with POF choose to live child-free.
Hormonal Replacement
It is important to initiate the hormonal replacement therapy after the diagnosis of POF, as untreated patients are at a great risk of bone loss due to increased osteoclast activities, resulting in osteopenia as well as osteoparosis.[4] Furthermore, most of the patients develop symptoms of estrogen deficiency, including vasomotor flushes and vaginal dryness, both of which respond to estrogen therapy effectively. There are several contraindications of estrogen supplement, including smokers over 35 years of age, uncontrolled hypertension, uncontrolled diabetes mellitus, or history of thromboemboli events. If the patient has strong family history of thromboemboli events, care must be taken to proceed with the hormonal replacement therapy. As the minimum, testing for Factor V Leiden, Protein C, and Protein S should be performed to ensure the low risk of developing thromboemboli events while on the estrogen replacement. The transdermal estradiol patch (typically 100 mcg) is commonly recommended because of several advantages. It provides the replacement by steady infusion rather than by bolus when taking daily pills. It also avoids the first-pass effect in the liver.[5]
Related Conditions
Impaired Ovarian Reserve
References
External links
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