Despite the name polycystic , women may or may not have cysts on their ovaries. Too much testosterone can also indicate the presence of tumors on the adrenal gland or ovaries—the main production center for these hormones in women.
For men, the testes and adrenal glands are the main producers. While testosterone levels typically decline in both women and men with age, menopause can produce deceptive results. A condition known as intersex is another cause for higher than normal testosterone levels in women. There is also much interconversion among steroid hormones.
The main precursor in the ovary is androstenedione, which is converted primarily to estrone, but which can also be converted to androgens. It is, therefore, reasonable to expect the symptoms of testosterone deficiency after menopause, since nearly half of the testosterone is manufactured by the ovary, although the post-menopausal ovary still produces some steroid hormones.
The recent finding of decreased testosterone and DHEA-S production in both pre- and post-menopausal women brings up the possibility of an enzyme defect causing decreased DHEA production.
DHEA is derived from 17 hydroxypregnenolone through the action of the enzyme 17, 20 lyase. If this enzyme is deficient, the DHEA would be low. However, because little attention has been paid publicly to female sexual dysfunction, this area has remain neglected, and only now is there understanding of such disorders in women.
This would put the number of women with decreased libido in the tens of millions in this country alone. How many of these women have decreased androgens is unknown, but the number is estimated to be between 10 and 15 million. Who may be affected? Most of the current clinical experience with androgens and androgen deficiency has been in post-menopausal women who complain of decreased sexual desire after cessation of menses, and are not helped by estrogen replacement therapy alone.
The question of androgen deficiency has largely been ignored in pre-menopausal women. Testosterone levels have usually been measured in this population only when looking for excess production in women complaining of facial hair, loss of scalp hair, infertility, or acne.
A recent presentation at the Female Sexual Function Forum meeting in Boston revealed that 36 premenopausal and 38 postmenopausal women complaining of decreased libido also had decreased total and free plasma testosterone levels as well as decreased levels of DHEA-S. Guidelines for assessing androgen deficiency Assays for plasma total testosterone have been available for over 40 years, and the levels are shown to decrease with age in women, as they do in men.
The relatively newer free testosterone assay has been in use for a decade, and whether by equilibrium dialysis or by direct radioimmunoassay, it is felt to be more accurate because it measures the amount of testosterone available for activity in the tissues.
However, very little data are available on normal ranges for these assays. Even the known data, using total testosterone, suffer from the general flaw that none of the women used for the normal ranges were screened for any type of sexual problems, including decreased sexual desire.
If the values are even slightly above the levels mentioned, it should be considered borderline, and a clinical trial of androgen may be in order if the symptoms are suggestive.
This hormone also decreases with age. A recent analysis has suggested two age-related curves, one for lean and one for obese women. There are no clear guidelines for evaluating women who might have androgen deficiency. In response to gonadotrophin-releasing hormone from the hypothalamus, the pituitary gland produces luteinising hormone which travels in the bloodstream to the gonads and stimulates the production and release of testosterone. As blood levels of testosterone increase, this feeds back to suppress the production of gonadotrophin-releasing hormone from the hypothalamus which, in turn, suppresses production of luteinising hormone by the pituitary gland.
Levels of testosterone begin to fall as a result, so negative feedback decreases and the hypothalamus resumes secretion of gonadotrophin-releasing hormone.
The effect excess testosterone has on the body depends on both age and sex. It is unlikely that adult men will develop a disorder in which they produce too much testosterone and it is often difficult to spot that an adult male has too much testosterone.
In both males and females, too much testosterone can lead to precocious puberty and result in infertility. In women, high blood levels of testosterone may also be an indicator of polycystic ovary syndrome. Women with this condition may notice increased acne , body and facial hair called hirsutism , balding at the front of the hairline, increased muscle bulk and a deepening voice.
There are also several conditions that cause the body to produce too much testosterone. The use of anabolic steroids manufactured androgenic hormones shuts down the release of luteinising hormone and follicle stimulating hormone secretion from the pituitary gland, which in turn decreases the amount of testosterone and sperm produced within the testes.
In men, prolonged exposure to anabolic steroids results in infertility, a decreased sex drive, shrinking of the testes and breast development. Liver damage may result from its prolonged attempts to detoxify the anabolic steroids. Dehydroepiandrosterone is primarily an adrenal product, regulated by adrenocorticotropic hormone ACTH and acting as a precursor for the peripheral synthesis of more potent androgens. Dehydroepiandrosterone is produced by both the ovary and adrenal, as well as being derived from circulating DHEAS.
Androstenedione and testosterone are products of the ovary and the adrenal.
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