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POLYCYSTIC OVARIAN SYNDROME (PCOS)
Polycystic
Ovarian Syndrome (PCOS) is the most common endocrine disorders of
women of reproductive age. Affecting approximately 6-10% of all
premenopausal women and approximately 70-90% of women with irregular
menstrual cycles, the classic symptoms of this disorder consist
of irregular periods, infertility, and excessive body and facial
hair. As a consequence of the overproduction of androgens (male
hormones) by the ovaries, additional symptoms of acne, obesity,
and male-pattern hair loss are seen together with symptoms of anovulation
like heavy menstrual flow and erratic, unpredictable onset of menses.
Some patients may demonstrate very mild or no symptoms of this disorder,
complaining only of irregular cycles. Other patients may demonstrate
all of the classic symptoms mentioned above.
Definition
of PCOS
Polycystic
ovarian syndrome (PCOS) is derived from the morphologic (appearance)
alterations that occur in the ovary. Failure to ovulate (to rupture
and release ovulatory eggs) on a monthly basis yields ovaries that
are literally, "covered with ovarian cysts." This failure
to ovulate healthy eggs results in infertility and a higher rate
of miscarriage after a positive pregnancy test.
Despite
our understanding of this most intriguing endocrine disorder of
women, scientists have been searching for an association among the
many facets of PCOS. Unfortunately, the pathophysiology of the various
disorders remains unknown. In the past, it was common for a woman
with infertility to have this diagnosis made during an infertility
evaluation. Today,
if the consequences of this disorder are left unattended, these
patients, infertile or not, will develop severe clinical problems.
A reduction in a woman's life expectancy occurs with no treatment
of this disorder as a consequence of cardiovascular disease and
diabetes mellitus.
Recent
PCOS Research
Recent
research has found growing concern that PCOS
is also associated with hyperinsulinemia (excess production
of insulin by the pancreas), insulin resistance, dyslipidemia (abnormality
of metabolism of fats), and hypertension. Risks of developing type
2 diabetes (non-insulin-dependent) and possibly, premature cardiovascular
disease is higher in these patients with insulin resistance. Other
consequences of anovulation include carcinoma of the endometrium
and possibly carcinoma of the breast. These facts have lead to a
new attitude towards this common female problem highlighting its
legitimate place in today's "modern preventive health care
of women."
PCOS
and Insulin Resistance
Insulin
resistance, characterized by a decrease in the ability of insulin
to stimulate glucose uptake to muscle and fat cells, as well as
to inhibit glucose production by the liver is a common feature of
women with PCOS. Up to 40% of women with PCOS demonstrate some degree
of impaired glucose tolerance as a result of insulin resistance.
A sign of severe insulin resistance exists known as acanthosis nigricans,
a condition in which dark velvety patches appear on the skin.
These
areas are usually seen around the back part of the neck ("ring
around the collar") and in other areas of the body where the
skin folds on itself forming creases. It appears likely that an
inherent, probably genetically determined ovarian defect is present
in women with PCOS, which makes the ovary susceptible to insulin
stimulation of androgen (male-like hormone) production. The insulin
resistance and hyperinsulinemia are primary events in PCOS that
somehow lead to hyperandrogenism and the subsequent reproductive
endocrine abnormalities.
It
goes without saying that the clinician must recognize the clinical
impact of PCOS and undertake therapeutic management of all anovulatory
patients to avoid these unwanted consequences. Use of birth control
pills, insulin sensitizing drugs, changes in life style patterns,
gonadotropin releasing hormone agonists, advanced diagnostic techniques
and assisted reproductive technologies are currently increasing
our understanding of this disorder. Our hope is to initiate preventative
measures early in young women's lives (teenage years) that yield
increased longevity with healthier and more reproductive outcomes.
PCOS-
Diagnosis
Diagnosis
of PCOS usually follows a high sense of suspicion in women with
irregular cycles who demonstrate mild forms of hyperandrogenism
and are having difficulty getting pregnant. To confirm the diagnosis,
blood testing of "the brain to ovary and ovary to brain signals"
are assessed on cycle days 3, 4 or 5. Measurement of FSH (follicle
stimulating hormone), LH (luteinizing hormone), and testosterone
give a characteristic pattern for the diagnosis of PCOS on most
occasions. The level of LH is normally equal to FSH in women without
PCOS. With this disorder, LH is often higher than FSH, up to 2-3
times, as well as high testosterone levels (> 50 ng/dl) revealing
high ovarian production. Checking serum progesterone levels on cycle
days 21-23 to confirm ovulatory function are unusually low (<
4 ng/dl), indicating ovulatory problems. Your clinician might also
recommend an ultrasound evaluation of the ovaries.
Insulin
resistance can be determined by obtaining a blood sample after a
12 hour fast for insulin and glucose. A glucose/insulin ratio of
< 4.5 will be used to define insulin resistance. Other tests
that might be used to help establish the diagnosis include a C-peptide
and a glycosolated hemoglobin (HbA1C).
All
right, now that I have your attention, how does PCOS affect a woman's
fertility? By affecting ovulation. These women do produce estrogen
from the ovaries in addition to testosterone, but the levels of
estrogen are lower than expected at the time of ovulation. Because
of the high level of LH and testosterone, follicular suppression
is caused within the ovary yielding poor or no ovulation with subsequent
loss of progesterone. Without a properly developed, healthy, fertilizable
egg and without estrogen and progesterone to secure a well-developed
endometrial bed for the ensuing pregnancy, infertility results.
In some women, an attempt to ovulate a poorly developed egg late
in the cycle yields a miscarriage from "a blighted ovum."
And
how does insulin resistance play a role in infertility? Again, by
affecting ovulation. Researchers now have found that high levels
of insulin can stimulate the activity of enzymes that are pivotal
to the manufacture of androgens in the ovary. They have also discovered
alterations or defects of these same enzymes that make them susceptible
to over stimulation by insulin. Consequently, high levels of insulin
or over stimulation of androgen receptors by insulin leads to follicular
atresia (suppression) of early developing eggs long before ovulation.
Therapeutic
options of PCOS depend on the severity of symptoms and the woman's
goal. Does the patient desire elimination of excess hair and/or
acne? Does she desire regular periods with normal bleeding? Does
she desire pregnancy? Is she at high risk of the metabolic abnormalities
associated with this disorder?
PCOS
Treatment
Many
treatment plans exist for PCOS. Among the most common are 1) weight
loss, 2) hormonal manipulations, 3) surgical treatments, 4) steroid
supplementation, 5) spironolactone, and more recently, 6) insulin
sensitizing medications. Your particular treatment plan will depend
on your goals.
Today,
we are truly entering a new era in our understanding and management
of women with polycystic ovaries and hyperandrogenism. We now have
a real opportunity "to make a difference in others lives"
by affecting the quality and quantity of life to be experienced
by these patients. Let us not only correct specific clinical consequences
of anovulation but, let us also reduce major adverse effects on
overall health.
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