Young woman smiling with glass of water after learning about normal estradiol levels in women

What Are Normal Estradiol Levels in Women?

Medically reviewed on Oct 20, 2023 by Neka Miller, PhD. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.


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There are many hormones at play when it comes to a woman’s menstrual cycle, her ovulation, and her ability to conceive. One of the most important hormones is known as estradiol.

Estradiol (E2) is the main form of estrogen in non-pregnant women. As one of the key hormones responsible for ovulation, estradiol is especially important for a woman’s reproductive health. Healthy estradiol levels in people assigned female at birth play a role in reproductive function and development, as well as other key markers of health, such as bone strength.

So, what is a normal estradiol level? Are my estradiol levels normal?

Keep reading to learn more about estradiol levels—normal and abnormal—in women at different stages of life, estradiol and fertility, and more.

Estradiol: Definition and Timeline

There are three main types of estrogen, a sex hormone that dominates in women and people assigned female at birth (AFAB). [1] These types of estrogen include [1]:

  • E1 or Estrone, which your body produces once you’ve reached menopause
  • E2 or Estradiol, which your body produces after puberty to support fertility
  • E3 or Estriol, which your body produces when you’re pregnant

A woman’s reproductive hormone levels are typically connected with her life stage. Before puberty, females have low amounts of sex hormones, meaning they have low serum (blood) estradiol and low serum testosterone.

Estradiol is critically involved in various phases of sexual development, from the onset of puberty to creating the conditions for a healthy pregnancy at peak fertility age. Levels of estradiol fluctuate throughout a person’s life, but the most obvious hormone level fluctuations occur over the course of the menstrual cycle. [1]

Follicular Phase Estradiol Levels

The follicular phase spans approximately days 1 to 14 of an average 28-day menstrual cycle, beginning with menstruation and ending with ovulation. During this phase, an egg cell develops in the follicle prior to its release (ovulation). Follicle-stimulating hormone (FSH) levels rise as the egg cell develops and fall abruptly after ovulation. [2]

In the follicular phase, estradiol levels normally follow the pattern below [2]:

  • Early in this phase, estradiol levels are low.
  • As the dominant follicle grows, it begins producing estradiol. Estradiol levels rise gradually at first, and then sharply rise 2 to 3 days before ovulation.
  • Estradiol levels peak just before two other important reproductive hormones surge: luteinizing hormone (LH) and FSH. Together, these hormones trigger ovulation.

Ovulation Phase Estradiol Levels

The ovulation phase starts after high estrogen levels and the surge of LH and FSH dispatch the mature egg from the dominant follicle. After ovulation, estradiol levels begin to drop. The low decline typically lasts for 1 or 2 days.

Luteal Phase Estradiol Levels

After ovulation, the luteal phase begins. The luteal phase spans approximately days 14 to 28 of an average 28-day cycle. [3]

During the luteal phase, healthy reproductive hormone levels adhere to the following pattern:

  • A specialized group of cells forms from the ruptured follicle and begins to secrete the hormone progesterone. Progesterone helps prepare the uterus for the potential implantation of a fertilized egg cell.
  • After their abrupt decline post-ovulation, estradiol levels gradually start to pick up again during the luteal phase. Over the 2 weeks before menstruation, estradiol levels peak and then decline to another low just before the uterine lining begins to shed. As estradiol levels fall, levels of progesterone fall as well.
  • At the end of the luteal phase, FSH levels begin to rise again. This signals your body is preparing to start the menstrual cycle again, stimulating another ovarian follicle and initiating the next follicular phase.

Why Do Estradiol Levels Matter for Fertility?

If you’re planning on starting or growing your family, estradiol tests can be used to help determine when you’re ovulating. By knowing when you ovulate, it’s easier to pinpoint your fertile window—the duration in the female reproductive cycle when conception is especially likely.

Are your estradiol levels normal? There are two main ways to test your estradiol levels [4]:

  • From a finger prick (dried blood spot)
  • From urine
  • From saliva

Home estradiol or E2 tests take a small sample of blood, typically at different stages of the menstrual cycle. By doing this, they can see how much E2 is in the bloodstream to determine normal baseline and peak estradiol levels throughout an individual’s cycle.

To see how your own estradiol levels rise and fall, consider taking an at-home fertility test. It’s easy to use and understand—and comes with everything you need to collect your samples from the convenience of home and send it to the lab for testing.

What Are Normal Estradiol Levels in Women?

Generally speaking, estradiol levels in women vary widely throughout different menstrual cycle phases. They’re also impacted by factors like:

  • Age
  • Pregnancy (pregnant women possess much higher levels of estradiol than non-pregnant women) [5]
  • Sample type

In fact, one key thing to keep in mind when it comes to testing for normal estradiol levels is that reference ranges can differ depending on the sample type, the day of collection, and the laboratory conducting the test.

Each laboratory will have their own unique reference ranges that are determined by their specific instruments, methodologies, and validations. This is why it’s very important to consider any results you may get in accordance with the reported reference range. Numbers alone may have slightly different clinical interpretations based on the lab that reported them, but this doesn’t mean any specific method lab is more or less correct than the others.

These variations are a normal part of the lab testing process, so it’s best to interpret your estradiol test results using the reference ranges provided by the laboratory used for testing.

High Estradiol Levels Causes

Elevated levels of estradiol can result from [6]:

  • Using a hormonal contraceptive
  • Certain hormone supplements
  • Having a high percentage of body fat
  • Excessive alcohol use or alcohol misuse disorder
  • Excessive or chronic stress
  • Liver disorders
  • Elevated levels of androgens, such as testosterone or progesterone

Elevated estradiol can also result from certain underlying medical conditions that cause the overproduction of estrogen, such as [6]:

  • Certain cancers, like breast cancer, ovarian cancer, or uterine cancer
  • Insulin resistance
  • Diabetes

PCOS is another condition that commonly results in high estradiol levels.6 In PCOS, many ovarian follicles simultaneously produce estradiol, causing exceptionally elevated estrogen levels. [6]

Low Estradiol Levels Causes

Low estrogen levels in women at certain points of the menstrual cycle are normal. However, exhibiting consistently low estradiol levels could indicate an underlying health condition, such as [7]:

  • Primary ovarian insufficiency (POI) – POI, which may also be called primary ovarian failure, is a condition that halts healthy reproductive function in women and people AFAB before the age of 40. [8] Even with proper hormonal stimulation, the ovaries cannot produce normal amounts of estradiol. [8] Ultimately, this suspends ovulation and creates the conditions for infertility. [8]
  • POI can sometimes result from a genetic condition, an autoimmune disorder, and can also arise due to toxin exposure like chemotherapy or cigarette smoke. [8]
  • Hypogonadotropic hypogonadism (HH) – HH is a condition that compromises the production of sex hormones by the brain. [9] The condition tends to occur when your body is under severe physical or psychological stress. [9]
  • Stressors could include excessive alcohol or drug use, excessive exercise, or nutritional deficiencies. [9] It may also result from a problem with the pituitary gland, which stimulates the production of FSH and LH hormones, or other parts of the brain. [9] Treatment typically involves hormonal therapy and, if possible, taking steps to reduce the amount of stress you’re under to improve both sexual function and your quality of life. [9]

If you’re in your late reproductive years, lower-than-average estradiol levels could simply mean you’re approaching a new phase of your reproductive life cycle—menopause. [7] In fact, a sustained rise in FSH levels generally signals the onset of menopause. Typically, an elevated FSH level for a period of more than 12 months indicates a transition into menopause.

If you’re trying to become pregnant at this stage, a trusted healthcare provider can provide some guidance on hormone therapy, estrogen therapy, and other treatments to support your fertility.

How Can I Find Out More About My Hormone Levels?

If you’re planning for pregnancy or just generally wondering, “What are normal estradiol levels?”, you can use the Everlywell at-home Women’s Fertility Test to easily check your hormone levels from the comfort of your own home.

With just a small sample of blood (collected with a simple finger prick), you can check your levels of 5 different hormones related to fertility: estradiol, luteinizing hormone, follicle-stimulating hormone, total testosterone, and thyroid-stimulating hormone. And you receive your results securely online—so you can easily access insights on your hormone balance whenever you want.

For an even more comprehensive look at your hormone levels, try the at-home Women’s hormone Test. By measuring 11 key biomarkers that play important roles in a woman’s health, the test can reveal any abnormal hormone levels that may be keeping you from feeling your best.


References
  1. Professional CC medical. Estrogen: Hormone, function, Levels & Imbalances. Cleveland Clinic. URL. Accessed October 10, 2023.
  2. Professional CC medical. Follicle-stimulating hormone (FSH): What it is & function. Cleveland Clinic. URL. Accessed October 10, 2023.
  3. Professional CC medical. Luteal phase of the menstrual cycle: Symptoms & length. Cleveland Clinic. URL. Accessed October 10, 2023.
  4. Estrogen levels test: Medlineplus medical test. MedlinePlus. URL. Accessed October 10, 2023.
  5. Estradiol (blood). Estradiol (Blood) - Health Encyclopedia - University of Rochester Medical Center. URL. Accessed October 10, 2023.
  6. Professional CC medical. High estrogen: Causes, symptoms, dominance & treatment. Cleveland Clinic. URL. Accessed October 10, 2023.
  7. Professional CC medical. Low estrogen: Causes, symptoms, diagnosis & treatment. Cleveland Clinic. URL. Accessed October 10, 2023.
  8. Primary ovarian insufficiency. Mayo Clinic. October 27, 2021. URL. Accessed October 10, 2023.
  9. Hypogonadotropic Hypogonadism. Pennmedicine.org. URL. Accessed October 10, 2023.
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