Info from: http://www.infertilitycentral.com/fertility/what-is-significance-of-fsh-levels.html
First, some background: FSH is an acronym for follicle stimulating hormone. FSH is one of several reproductive hormones
that our bodies should be producing at certain ranges during certain times in each ovulatory cycle, in order for optimal ovulation
to occur. FSH, which is produced by our pituitary gland, does what its name implies -- it stimulates follicles to grow. Within
our ovaries, follicles are the structures that contain the egg cells.
So given all of the above, FSH is a pretty important hormone to the conception process. A number of things can go wrong
in a body that would lead to inadequate production or overproduction of this and other hormones. When the ranges that have
been determined as optimal for conception are thrown off one way or another, a problem can result.
An example of how delicate this optimal balance is: While those of us who are learning about infertility tend to worry
most about FSH levels that are too high (and I'll explain why later), it is also the case that too little FSH can hamper
conception. Hypothalamic anovulation (or lack of ovulation due to a malfunction of the hypothalamus gland) is a result of
too little or no FSH production.
If female infertility is suspected, basic testing of what is called "ovarian reserve" is done. Ovarian reserve refers to
a woman's egg supply, thereby being somewhat predictive of her reproductive capability. Testing a woman's level of FSH in
her blood on the third day (Day 3) of a cycle has been found to be considerably predictive of her fertility within an
Going back to our more common concern around here, that of too-high FSH levels: according to Dr. Robert Jansen, author
of Overcoming Infertility, FSH levels that are high, particularly on more than one occasion, "means that the pituitary
gland is trying to overcome -- to compensate for -- an absence of responsive follicles in the ovaries, which is just what
happens naturally at menopause..." Overly abundant FSH is one of the hallmarks of primary or premature ovarian failure, sometimes
referred to as early menopause.
How high is too high?
First, you should know that lab values may vary, so you'll have to talk with your own medical team about the ranges that
their lab uses and what they take it to mean. Second, stay aware of things such as possibility of lab error, as well as the
fact that FSH (and other hormone) levels can fluctuate as affected by environment, stress, illness, etc. Last, in most cases,
one FSH test cannot predict all by itself a woman's fertility.
Generally, the lower the FSH, the better for fertility. Most docs like to see numbers below 15 mIU/ml.
As far as timing of the test and fluctuation of FSH: it is not necessary for the test to be run on exactly Day 3. Depending
on the individual, there should be only slight fluctuation of FSH levels from days 2 through 5. What is important is
fluctuation of the hormone levels from cycle to cycle, rather than fluctuations within a given cycle. It is believed that
when a woman's hormones maintain relative sameness over several cycles, she is more apt to be producing high quality eggs.
Some experts now believe that a woman's fertility is only as good as her highest FSH level. Even if her hormones return
to normal levels after measuring high FSH in the previous cycle, her fertility is diminished, at least during that follow-up
The question of FSH and other ovarian reserve testing is one of great concern for most women undergoing evaluation for
conception difficulties. It is important to understand as fully as possible the entire hormonal picture, how the body's endocrine
system and responses lead to fertility or infertility, rather than relying on numerical results from one test. There are many
more ways (in addition to FSH testing) to determine ovarian reserve, and women should approach the possible diagnosis of premature
ovarian failure with educated skepticism.
FSH Blood Level Measurement
This is the key test to determine
whether or not you are in menopause. A sample of your blood is taken to measure the levels of FSH -- follicle stimulating
hormone -- in your blood. Because your FSH levels rise when your ovaries stop producing enough estrogen, high FSH levels can
signal that your body is entering menopause.
- Normal FSH day 3 value is 3-20 mlU/ml
- FSH levels above 10 to 12 mlu/ml indicate that your ovaries are starting to fail.
In other words, this means that you are in perimenopause -- the beginning stages of menopause when you notice physical symptoms,
but before you have stopped having a period for a year, or have "diminished ovarian reserve"
- Higher FSH levels -- levels about 30 to 40 or above -- are usually taken to signal
menopause or ovarian failure. You may even be getting periods with your FSH levels this high, but it still is a sign
that your body isn't producing enough estrogen to maintain regular ovarian function.
- Keep in mind that you may end up with FSH levels that are well in the post-menopausal
range, but still be getting a period. This is one of the things that differentiates premature menopause or premature
ovarian failure from "regular" menopause (i.e. menopause that occurs to older women after a full year without a period).
Yet again, this hammers home the unfortunate fact that you may indeed be in premature menopause even if you're having periods.
Once your FSH levels have reached a certain height for a period of time, it's highly unlikely that they'll drop back to premenopausal
levels. In my case, even after my FSH was tested at over 150, I had apparently normal periods for eight months.
Then when I was retested -- hoping that somehow my body had snapped back to normal, I learned that my FSH level had dropped.
. . . but only to 126. Since my FSH levels had been well above 35 for over a year, I finally accepted that my ovaries
- As mentioned above, because hormone levels can and do fluctuate, remember that
the FSH is far from foolproof. Some women can test with a high FSH, then revert to normal levels the next month...and
so on. Again, it's generally wise to get tested more than once.
Entries taken from individuals from the web:
1. First of all, FSH does not indicate egg quality. Age is the "best" predictor of egg quality but it's not a perfect indicator.
FSH is, at best, a predictor of how someone will respond to IVF & stimulants to produce ovulation. And there are many
in the field who are beginning to take the view that while FSH is an indicator, it's not even the best indicator of response
to IVF. Antral follicle count may be a better indicator (done at CD3 by ultrasound).
2. When i had found out i had just gotten married and started TTC. after two months off the pill, i started suffering hot
flashes and never got my period. (the pill had masked my symptoms for years). I went to obgyn who ran tests and my FSH came
back at 180 and told me I was post-menopausal. he then sent me to an RE who diagnosed me with POF. In simple terms, POF occurs
when the ovaries don't respond to the pituitary gland's signal (FSH) to begin creating folicles