Hormone Levels and PCOS


Remember that PCOS cannot be diagnosed by symptoms alone. PCOS is a very complicated endocrine disorder.

Remember that PCOS cannot be diagnosed by symptoms alone.  PCOS is a very complicated endocrine disorder.  Blood tests to measure hormone levels, an ultrasound to look at your reproductive organs and thorough personal and family histories should be completed before a PCOS diagnosis is confirmed. Depending on your symptoms, your physician will determine exactly which tests are necessary. Assessing hormone levels serves two major purposes. First of all, it helps to rule out any other problems that might be causing the symptoms. Secondly, together with an ultrasound and personal and family histories, it helps your doctor confirm that you do have PCOS. Most often, the following hormone levels are measured when considering a PCOS diagnosis:

  • Lutenizing hormone (LH)
  • Follicle-stimulating hormone (FSH)
  • Total and Free Testosterone
  • Dehydroepiandrosterone sulfate (DHEAS)
  • Prolactin
  • Androstenedione
  • Progesterone.

Other hormones that may be checked include:

  • estrogen
  • thyroid stimulating hormone (TSH)

In addition, glucose, cholesterol (HDL, LDL and triglicerides) levels might also be assessed.

Lutenizing Hormone (LH) and Follicle Stimulating Hormone (FSH)

LH and FSH are the hormones that encourage ovulation. Both LH and FSH are secreted by the pituitary gland in the brain. At the beginning of the cycle, LH and FSH levels usually range between about 5-20 mlU/ml. Most women have about equal amounts of LH and FSH during the early part of their cycle. However, there is a LH surge in which the amount of LH increases to about 25-40 mlU/ml 24 hours before ovulation occurs. Once the egg is released by the ovary, the LH levels goes back down.

While many women with PCOS still have LH and FSH still within the 5-20 mlU/ml range,  their LH level is often two or three times that of the FSH level. For example, it is typical for women with PCOS to have an LH level of about 18 mlU/ml and a FSH level of about 6 mlU/ml (notice that both levels fall within the normal range of 5-20 mlU/ml).  This situation is called an elevated LH to FSH ratio or a ratio of 3:1. This change in the LH to FSH ratio is enough to disrupt ovulation. While this used to be considered an important aspect in diagnosing PCOS, it is now considered less useful in diagnosing PCOS, but is still helpful when looking at the overall picture.


All women have testosterone in their bodies. There are two methods to measure testosterone levels:

  • Total Testosterone
  • Free Testosterone

Total testosterone refers to the total amount of all testosterone, including the free testosterone, in your body.  The range for this is 6.0-86 ng/dl.  Free testosterone refers to the amount of testosterone that is unbound and actually active in your body.  This amount usually ranges from 0.7-3.6 pg/ml.  Women with PCOS often have an increased level of both total testosterone and free testosterone.  Furthermore, even a slight increase in testosterone in a woman’s body can suppress normal menstruation and ovulation.


DHEA-S or dehydroepiandrosterone is another male hormone that is found in all women. DHEA-S is an androgen that is secreted by the adrenal gland. It is normal for women to have DHEA-S levels anywhere between 35-430 ug/dl.  Most women with PCOS tend to have DHEA-S levels greater than 200 ug/dl.


Prolactin is a pituitary hormone that stimulates and sustains milk production in nursing mothers. Prolactin levels are usually normal in women with PCOS, generally less than 25 ng/ml. However, it is important to check for high prolactin levels in order to rule out other problems, such as a pituitary tumor, that might be causing PCOS-related symptoms.  Some women with PCOS do have elevated prolactin levels, typically falling within the 25-40 ng/ml range.

Androstenedione (ANDRO)

ANDRO is a hormone that is produced by the ovaries and adrenal glands. Sometimes high levels of this hormone can affect estrogen and testosterone levels. Normal ANDRO levels are between 0.7 ­ 3.1 ng/ml.


Progesterone is produced by the corpus luteum after ovulation occurs.  Progesterone helps to prepare the uterine lining for pregnancy.  For women with PCOS, especially those who are trying to become pregnant using fertility medications, Progesterone levels are checked about 7 days after it is thought that ovulation occurred.  If the Progesterone level is high (usually greater than 14 ng/ml) this means that ovulation did indeed occur and the egg was released from the ovary.  If the progesterone level is low the egg was probably not released. This test is especially important because sometimes women with PCOS can have some signs that ovulation is occurring however, when the progesterone test is done, it shows that ovulation did not occur. If this happens, your body is may be producing a follicle and preparing you to ovulate, but for some reason the egg is not actually being released from the ovary.  This information helps your physician possibly adjust fertility medication for the next cycle to encourage the release of the egg.


Estrogen is the female hormone that is secreted mainly by the ovaries and in small quantities by the adrenal glands.  The most active estrogen in the body is called estradiol.  A sufficient amount of estrogen is needed to work with progesterone to promote menstruation. Most women with PCOS are surprised to find that their estrogen levels fall within the normal range (about 25-75 pg/ml).  This may be due to the fact that the high levels of insulin and testosterone found in women with PCOS are sometimes converted to estrogen.


TSH stands for Thyroid Stimulating Hormone and is produced by the thyroid, a gland found in the neck. Women with PCOS usually have normal TSH levels (0.4-3.8 uIU/ml).  TSH is checked to rule out other problems, such as an underactive or overactive thyroid, which often cause irregular or lack of periods and anovulation.

Insulin and Glucose

Due to the recent research that PCOS is probably caused by insulin resistance, physicians are beginning to check glucose levels as a factor when diagnosing PCOS.   Most women with polycystic ovary syndrome should have an Fasting Plasma Glucose Test and a Glucose Tolerance Test at diagnosis and periodically thereafter, depending on risk factors.  A high glucose level can indicate insulin resistance, a diabetes-related condition that contributes to PCOS.


Researchers are also beginning to notice a connection between PCOS and heart disease; therefore, some physicians may want to look at your cholesterol levels when diagnosing and treating PCOS. Women with PCOS have a greater tendency to have high cholesterol, a major risk factor for developing heart disease. Cholesterol is a fat-like substance normally used by the body for form cell membranes and certain hormones.  A high cholesterol level is considered greater than 200. Also, since the levels of good (high-density lipoproteins or HDL) and bad (low-density lipoproteins or LDL) are sometimes more indicative of a woman’s risk for developing heart disease, these levels might also be assessed.

Too much bad cholesterol tends to increase the risk for plaque to build up in the arteries which can lead to a heart attack. Too much good cholesterol is believed to remove the cholesterol from building up in the arteries.  Women with PCOS tend to have less good cholesterol and more bad cholesterol.  In addition, triglyceride levels, another component of cholesterol, tend to be high in women with PCOS which further contributes to the risk of heart disease.  Even if your physician does not check your cholesterol levels when diagnosing PCOS, it is a good idea to have these levels checked periodically since women with PCOS have a greater chance of developing high cholesterol which can lead to heart disease.

More About Hormone Levels

It is important to remember that with all women, hormone levels can very greatly.  It is also important to mention that since the “normal” ranges vary greatly for some hormones (especially since each lab sets its own “normal” values for these hormones), some women with PCOS have hormone levels that appear within the “normal” range, but still suffer from symptoms and still might have PCOS. This is especially true with Testosterone , DHEAS, and LH levels.  Unfortunately, many physicians are not familiar enough with PCOS to understand that even small changes in hormone levels can cause PCOS-related symptoms.  If you have a Testosterone level of >40 ng/ml, DHEAS level of >200 ug/dl or a LH level that is two or three times that of your FSH level (LH and FSH levels should be roughly equal), seek the advice of a specialist since there is still a good possibility you might have PCOS.


Angela Best-Boss and Evelina Weidman Sterling, authors of Living with PCOS with Richard Legro MD (Editor)

Related Videos
raanan meyer, md
Fertility counseling for oncology patients | Image Credit: allhealthtv.com
Fertility treatment challenges for Muslim women during fasting holidays | Image Credit: rmanetwork.com
The importance of maternal vaccination | Image Credit: nfid.org.
Haywood Brown, MD | Image credit: © USF Health
Beth Garner, MD, MPH
Related Content
© 2024 MJH Life Sciences

All rights reserved.