What Hormone Imbalance Tests Reveal About Women's Health

A blood test for female hormones can reveal important information about your health. They can detect fertility problems, where you are in your menstrual cycle, or whether you're starting perimenopause.

Hormone tests also can play a role in diagnosing medical conditions such as thyroid disease or diabetes. In some instances, they can show how well a medication is working.

This article looks at the tests done for each sex hormone, when tests are needed, what's considered normal and abnormal, and what the results could mean.

What's Being Tested?

Hormone blood tests can look at several key female hormones:

• Estrogen
• Progesterone
• Follicle-stimulating hormone (FSH)
• Testosterone/DHEA
• Thyroid hormones

In most cases, healthcare providers use hormone test results combined with other factors—such as symptoms, medical history, and other test results—to reach a diagnosis.

Estrogen

Estrogen isn't a single hormone. You have many types of estrogens. Only three of them are commonly tested:

• Estrone (E1): The main post-menopausal hormone
• Estradiol (E2): The main female hormone before menopause and outside of pregnancy
• Estriol (E3): A form that increases during pregnancy

E2 is the most often tested form. It's the major hormone responsible for sexual function and also plays a major role in:

• Healthy bones
• Female characteristics
• Other aspects of health

Estradiol is primarily produced by the ovaries and levels vary throughout the menstrual cycle. They're highest at ovulation and lowest at menstruation.

E2 levels slowly decrease as you age. The largest drop occurs at menopause when the ovaries "switch off."

Everyone has some estradiol in their bodies, regardless of their biological sex.

When Estrogen May Be Tested

You may need an estrogen test if you have symptoms of an estrogen-related condition or:

• You're having trouble getting pregnant
• Your periods are irregular
• Puberty appears to be delayed, regardless of biological sex
• You're having menopause symptoms
• You have vaginal bleeding after menopause
• You're biologically male but displaying female characteristics (such as developing breasts)

Estrogen Test Results

What's considered normal for estradiol levels depends on your menstrual cycle and phase of life. Testing for fertility looks at three phases of the menstrual cycle:

• Follicular phase lasts from the first day of your period until ovulation, usually about 14 days. It's named for the follicle housing the egg before it's released during ovulation.
• Periovulatory phase is an approximately three-day period around the time of ovulation.
• Luteal phase lasts from ovulation until the start of menstruation. After ovulation, the follicle releases estrogen and progesterone to prepare your uterus for a fertilized egg to implant.
  

Estrogen levels are measured in picograms (one-millionth of a gram) per mililiter (pg/mL).

What the Results Mean

Low estrogen levels may be a sign of:

• Polycystic ovary syndrome (PCOS)
• Decreased pituitary function (hypopituitarism)
• Anorexia nervosa
• Low body fat

Certain medications, such as Clomid (clomiphene, a fertility drug), also can cause a decline in estrogen levels.

High estrogen levels may occur with conditions such as:

• Obesity
• Light or heavy menstrual bleeding
• Worsened premenstrual syndrome
• Fatigue
• Loss of sex drive

Certain medications are also known to increase estrogen levels. These include steroid hormones, phenothiazines, tetracycline antibiotics, and ampicillin.

Progesterone

Progesterone is essential for regulating menstruation and fetal development. During the luteal phase, it helps prepare the uterus to receive a fertilized egg. What happens next depends on whether the egg is fertilized:

• If the egg is not fertilized, progesterone levels plummet, and a new menstrual cycle begins.
• If the egg is fertilized, progesterone levels remain high. This stimulates the growth of blood vessels that supply the lining of the uterus (endometrium) and makes glands in the endometrium release nutrients to nourish the developing embryo.

When Progesterone Levels May Be Tested

You may need a progesterone test to determine:

• Whether you're ovulating normally
• Why you're having trouble getting pregnant
• Your risk of miscarriage or other pregnancy complications
• If you have a pregnancy outside of the uterus (ectopic pregnancy)

Progesterone Test Results

As with estrogen, what's considered normal for progesterone depends on the timing of the test. Midway through the menstrual cycle, progesterone levels start climbing. Between six and 10 days later, if there's no fertilized egg, levels drop off.

If the egg is fertilized, levels rise through the earliest stage of pregnancy.

Progesterone levels are measured in nonograms per mililiter (ng/mL) or nanomoles per liter (nmol/L).

What the Results Mean

If progesterone levels are low during pregnancy, it could be a sign that you're at risk of miscarriage or premature labor. You may be given a synthetic form of progesterone to prevent early labor.

High progesterone levels usually do not signal any health problems unless they continue for a long time. In those instances, high levels may indicate an increased risk of breast cancer.

Follicle Stimulating Hormone

Follicle-stimulating hormone (FSH) is produced by the pituitary, a pea-sized gland in the brain. FSH stimulates the growth of an egg in the ovary to get it ready for fertilization.

FSH can be checked with either blood or urine tests. Healthcare providers may look at a single sample or, to look for fluctuations, several samples taken over a 24-hour period.

The pituitary gland produces more FSH when estrogen and other hormone levels begin to drop before menopause, when the ovaries are losing their reproductive potential.

When FSH Levels May Be Tested

In adult females, the FSH test may be used in diagnosing:

• Abnormal menstrual bleeding
• Infertility
• The start of perimenopause or menopause
• Ovarian function issues and PCOS
• Pituitary gland tumors
• Ovarian cysts

FSH Test Results

This hormone also changes over the course of your menstrual cycle and lifetime.

FSH is measured in milli-international units per milliliter (mIU/mL).

What the Results Mean

Abnormal FSH levels are often caused by a disease of the pituitary gland or the hypothalamus (a part of the brain). The hypothalamus has several functions, including:

• Balance
• Temperature regulation
• Hunger and satiation

These glands can be affected by PCOS, cancer treatment, a congenital defect (a condition you're born with), or other diseases and disorders.

Testosterone and DHEA

While testosterone is usually regarded as the "male sex hormone," it's also part of the female hormonal makeup. In females, testosterone is produced in the ovaries and adrenal glands. Most of it is then converted to estradiol with the help of an enzyme called aromatase.

Dehydroepiandrosterone (DHEA) is also classified as an androgen, but it is normally present in females as well.

When Testosterone/DHEA Levels May Be Tested

You may need a testosterone or DHEA test because of:

• Irregular or missed periods
• Possible ovarian conditions, including PCOS and ovarian cancer
• Weight gain
• Acne
• Development of male traits (excess hair growth, male pattern baldness, deepening voice)
• Infertility
• Decreased sex drive

Testosterone/DHEA Test Results

Testosterone doesn't fluctuate like female hormones, so the timing of tests isn't important. Testosterone is measured in nanograms per deciliter (ng/dL) or nmol/L.

Normal DHEA levels depend on your age. It's measured in micrograms per deciliter (mg/dL) or micromoles per liter (mmol/L).

What the Results Mean

High testosterone could mean steroid abuse, PCOS, cancers of the adrenal glands or ovaries, and congenital adrenal hyperplasia.

Low libido is associated with low levels of testoterone. A drop in testosterone can also indicate perimenopause.

High DHEA levels on blood tests may be a sign of conditions such as congenital adrenal hyperplasia or cancer of the adrenal gland.

Thyroid Hormones

Thyroid function is determined by the levels of a group of hormones. These hormones are produced by the pituitary and thyroid glands. The three main ones are:

• Thyroid-stimulating hormone (TSH): A pituitary hormone that tells the thyroid gland to produce more hormone
• Thyroxine (T4): An inactive thyroid hormone that can be converted to an active state
• Triiodothyronine (T3): The active thyroid hormone, most of which comes from converted thyroxine

Thyroid function tests are often included in a female hormone panel because thyroid diseases are more common in women than men. It may also be included to examine whether the thyroid is affecting fertility and pregnancy.

When Thyroid Levels May Be Tested

You may need a thyroid hormone test if you have symptoms of either an underactive thyroid (hypothyroidism) or an overactive thyroid (hyperthyroidism).

Hypothyroidism symptoms include:

• Fatigue
• Unintended weight gain
• Puffy face
• Intolerance of cold
• Pain in the joints and muscles
• Constipation
• Dry skin
• Dry, thinning hair
• Decreased sweating
• Heavy or irregular menstrual periods
• Fertility problems
• Depression
• Slow heart rate
• Goiter (enlarged thyroid gland causing a lump in the front of your throat)

Hyperthyroidism symptoms include:

• Anxiety
• Fatigue
• Frequently feeling cold or hot
• Irregular or light menstrual period
• Hair loss
• Unintended weight loss or gain
• Tremors
• Rapid heart rate
• Bulging eyes
• Goiter
• Hyperactivity
  

Thyroid Test Results

Healthcare providers may use TSH alone or a combination of TSH, T4, and T3 tests to diagnose thyroid disorders.

TSH is measured in milli-international units per liter (mIU/L). There's a range for non-pregnant females as well as trimester-specific ranges in pregnancy.

T4 is measured in micrograms per deciliter (µg/dL). T3 is measured in nanograms per deciliter (ng/dL).

What the Results Mean

Interpreting TSH results can be confusing. That's because high TSH means low thyroid activity, and low TSH means high thyroid activity.

Your provider may look at TSH alone or all three hormones together in order to reach a diagnosis.

If results start out with low TSH and high thyroid hormones and then reverse with further testing, it indicates thyroiditis, which is inflammation of the thyroid gland.

Summary

Hormone tests are often done as part of regular blood work, but your healthcare provider may order them if you're having menstrual issues, changes in sex characteristics, fatigue, loss of sex drive, or problems getting pregnant.

Providers may specifically check estrogen, progesterone, FSH, testosterone/DHEA, and thyroid hormone levels. Abnormal readings can indicate that you have a condition such as PCOS, ovarian cysts, thyroid disease, or, possibly, cancer.

Tests are one step in the process of diagnosing a condition. If the results are concerning, your provider may order additional tests.