Estrogen Dominance

Estrogen Dominance


What is estrogen?

Your body’s hormones are like a seesaw. When they’re perfectly balanced, your body works as it should. But when they’re unbalanced, you may begin experiencing problems.

Estrogen is known as the “female” hormone. Testosterone is known as the “male” hormone. Although each hormone is identified with a specific sex, both are found in women and men. On average, women have higher levels of estrogen and men have more testosterone.

In women, estrogen helps initiate sexual development. Along with another female sex hormone known as progesterone, it also regulates a woman’s menstrual cycle and affects her entire reproductive system. In premenopausal women, estrogen and progesterone levels vary from one stage of the menstrual cycle to another.

In men, estrogen also plays an important role in sexual function.

Causes of high estrogen

High levels of estrogen can develop naturally, but too much estrogen can also result from taking certain medications. For example, estrogen replacement therapy, a popular treatment for symptoms of menopause, may cause estrogen to reach problematic levels.

Your body may also develop low testosterone or low progesterone levels, which can upset your hormonal balance. If you have estrogen levels that are abnormally high relative to your progesterone levels, it’s known as estrogen dominance.

Symptoms of high estrogen in women

When your body’s estrogen and testosterone levels aren’t balanced, you may begin developing certain symptoms. In women, potential symptoms include:

  • bloating
  • swelling and tenderness in your breasts
  • fibrocystic lumps in your breasts
  • decreased sex drive
  • irregular menstrual periods
  • increased symptoms of premenstrual syndrome (PMS)
  • mood swings
  • headaches
  • anxiety and panic attacks
  • weight gain
  • hair loss
  • cold hands or feet
  • trouble sleeping
  • sleepiness or fatigue
  • memory problems

Diagnosing high estrogen

If your doctor suspects that you might have high estrogen, they’ll likely order a blood test to check your hormone levels. A trained professional will collect a sample of your blood to be tested in a laboratory. The results will indicate if your estrogen levels are too low or too high. Blood estrogen levels are measured in pictograms per milliliter (pg/mL).

There are three types of estrogen: estradiol, estriol, and estrone. Estradiol is the primary female sex hormone. Estriol and estrone are minor female sex hormones. Estriol is nearly undetectable in women who aren’t pregnant.

Normal estrogen levels in women

According to Mayo Medical Laboratories, the following estrone and estradiol levels are considered normal for women:



Prepubescent female

Undetectable–29 pg/mL

Undetectable–20 pg/ml

Pubescent female

10–200 pg/mL

Undetectable–350 pg/ml

Premenopausal adult female

17–200 pg/mL

15–350 pg/ml

Postmenopausal adult female

7–40 pg/mL

<10 pg/ml

In premenopausal girls and women, estradiol levels vary widely throughout the menstrual cycle.

Treatment for high estrogen

To manage high estrogen or estrogen dominance, your doctor might prescribe medications, recommend surgery, or encourage you to adjust your diet.


If you develop high estrogen while undergoing hormone therapy, your doctor might change your hormone therapy plan. This might help your body achieve a healthier hormone balance.

If you have a type of cancer that’s sensitive to estrogen, high estrogen levels can make the cancer worse. Your doctor might prescribe medications to block cancer cells from binding to estrogen. For example, they might prescribe tamoxifen.

Alternatively, they might prescribe an aromatase inhibitor. This type of medication stops the enzyme aromatase from converting androgens into estrogen. This class of drug includes:

  • anastrozole (Arimidex)
  • exemestane (Aromasin)
  • letrozole (Femara)

In other cases, they might prescribe a medication that stops your ovaries from producing estrogen. For example, they might prescribe:

  • goserelin (Zoladex)
  • leuprolide (Lupron)


If you have a type of cancer that’s sensitive to estrogen, your doctor might also recommend an oophorectomy. This is a type of surgery used to remove ovaries. Since ovaries produce most of the estrogen in women’s bodies, removing them lowers estrogen levels. This causes what is known as surgical menopause.

Your doctor might also recommend oophorectomy if you’re at very high risk of developing breast or ovarian cancerYou may be at very high risk if one or more of the following are true:

  • You have a strong family history of breast cancer or ovarian cancer.
  • You test positive for a specific mutation in the BRCA1 or BRCA2 gene.
  • You test positive for a specific mutation in other genes associated with cancer risk.

According to the National Cancer Institute (NCI), removing both ovaries appears to reduce the risk of breast cancer in very-high-risk patients by about 50 percent.

Your doctor can also use radiation therapy to make your ovaries inactive.


To help lower your estrogen levels, your doctor might recommend changes to your eating habits. For example, they might encourage you to eat a low-fat and high-fiber diet. They might also encourage you to lose excess weight.