What is estradiol?

Estradiol is a type of estrogen that’s produced primarily from the ovaries but in lesser amounts by the adrenal glands and fatty tissue. As one of the primary sex hormones, it plays a key role in regulating your menstrual cycle. Additionally, estradiol is essential for healthy cardiovascular function and for helping maintain pregnancy. Interestingly, it isn’t only a female hormone; it’s also present in men, albeit in much smaller quantities. 

What does estradiol do?

Estradiol has many functions within the reproductive system, but it doesn’t stop there. Some of its key functions include:

• Regulating the menstrual cycle
• Maintaining bone density
• Mood regulation 
• Sexual development

Maintaining normal estradiol levels by age is essential to ensuring your body functions properly. For women trying to conceive, estradiol plays an important role in preparing the uterus for implantation by thickening the uterine lining. It does this during the follicular phase and then in the luteal phase, following ovulation, working together with progesterone to prepare the body for conception.

Measuring estradiol levels – blood test results

Estradiol levels in women can vary, but ensuring they’re where they need to be is important for your reproductive health. Many women ask the question, “What should my estradiol levels be?” An estradiol blood test measures how much of the hormone is in your blood. Also called an E2 test, it only requires a small amount of blood and is considered relatively painless. Your estradiol levels can be measured in picograms per milliliter (pg/ml) in picomoles per liter (pmol/L), and they vary throughout different stages of a woman’s life and from lab to lab. What are normal estradiol levels by age?

What are normal estradiol levels in females by age?

Please keep in mind that the following values 

Pubescent females

Estradiol’s normal range for pubescent females is undetectable, up to 15 pg/ml. However, as puberty progresses, these normal range levels rise with each Tanner stage. 

Reproductive-age females

The estradiol blood test’s normal range for reproductive-age females is 20 pg/ml to 750 pg/ml. However, in women who are pregnant, these numbers skyrocket. Estradiol levels in pregnancy vary by trimester. 

• First trimester – The estradiol levels in early pregnancy indicate that normal levels range between 188–2497 pg/ml on the chart.
• Second trimester – Women in their second trimester should have levels between 1278–7192 pg/ml on the estradiol chart.
• Third trimester – Normal estradiol levels for women in their third trimester are from 3460–6137 pg/ml. 

Estradiol levels naturally fluctuate during your menstrual cycle and can be an indicator of what phase you’re in. Normal estradiol levels for fertility are:

• During the follicular phase – During the first part of the follicular phase, estradiol remains under 50 pg/ml. Estradiol levels during your period are usually the lowest in your cycle and begin to rise during the late follicular stage to 20 pg/ml to 350 pg/ml.
• Before ovulation – Your estradiol levels are their highest right before ovulation, reaching anywhere between 150 pg/ml and 750 pg/ ml.
• During the luteal phase – After ovulation, when you enter the luteal phase, your estradiol levels drop to 30 pg/ml to 450 pg/ml.

However, please note that in your lab, reference ranges can be different.

Perimenopausal females

There are three stages of perimenopause: early, late, and menopause, which includes the 12 months after the last period. Estradiol levels during perimenopause and menopause massively dip from that of reproductive-age women. 

After menopause, which means after a year since the last period, estradiol levels drop back to undetectable to 20 pg/ml, reaching similar levels to that of pubescent females.

What does low estradiol mean?

If your estradiol test results show low estradiol levels, it could indicate you have pituitary gland issues, ovarian failure, are entering into early perimenopause, or, for those who are pregnant, a failing pregnancy. Low estradiol levels can have a major impact on your menstrual cycle; if your estradiol levels are low, it could lead to infertility.

What does high estradiol mean?

While low estradiol levels can indicate reproductive issues, so can elevated estradiol. With estradiol levels, high concentrations can also cause water retention, breast tenderness and overgrowth of the uterine lining. Causes of high estradiol can include fertility treatments, certain medications, obesity, smoking, age, and a high-fat diet. 

Tips on monitoring your estradiol levels to promote overall well-being

When it comes to monitoring your estradiol levels, you’ll want to work closely with your doctor to ensure that you test at the right time. If you have an irregular cycle, your doctor can decide the best time to test to get the most accurate results. Here are a few tips to keep in mind when monitoring your estradiol levels to help promote your overall well-being.

Focus on the timing

With estradiol testing, timing is the most crucial element for accuracy. Your blood test could be done on the third day of your menstrual cycle since that’s widely considered the time of follicle recruitment. In addition, your doctor may recommend checking estradiol levels near the time of ovulation and in the middle of your luteal phase.

State all medications

Certain medications can impact your estradiol levels, so it’s crucial to tell your doctor about any prescribed or over-the-counter medications you’re taking.

Be consistent

If you’re repeating your tests, consistency is key. Testing at the same time, with the same lab, puts you in the best position to get the most accurate results.

Note your symptoms

If you believe your estradiol levels are imbalanced, it’s important to take note of your symptoms and alert your doctor. These can include anything from mood swings and irregular periods to changes in libido.

Maintain a healthy lifestyle

When it comes to overall hormone health, maintaining a healthy lifestyle is essential. Stress management, regular exercise, and a balanced diet can help you feel your best. 

Understanding how estradiol impacts your overall body and well-being can help you take control of your hormone health. Depending on your age, an estradiol level chart can help you monitor your levels and determine if and when you should consult your doctor. 

The Hormona app is your personal at-home hormone tracker that makes it easy to monitor your hormone levels from the comfort of your home. This award-winning tool gives you comprehensive insights into your hormones so you can understand your body better and feel your best.

FAQ

How do I read my estradiol results?

Once you’ve taken your estradiol test, your results are displayed on an estradiol level chart. The hormone is reported in picograms per milliliter (pg/ml) and will generally be categorized by your sex and reproductive status.

Is estradiol the same as estrogen?

Yes, there are three types of estrogen: estrone (E1), estradiol (E2), and estriol (E3), each produced at different stages of a woman’s life.

Does estradiol cause weight gain?

Estradiol is believed to be responsible for water retention, but there could be other factors in place. During adolescence, perimenopause, and menopause, low estradiol levels cause weight gain since adipose tissue is one of the sources of estrogen; this may serve as a compensatory mechanism for producing more estrogen.  

Does high estradiol in women mean infertility?

High estradiol levels don’t mean infertility. However, during PCOS, which is a condition when ovulation is commonly absent, levels of estradiol can be elevated, as there are multiple follicles that produce estrogen but cannot rupture and release an egg.

What’s worse, low or high estradiol?

Typically, low estradiol levels are thought to be worse than high ones since they often include worse symptoms like heart disease, bone loss, and menopausal issues. High estradiol is still not good since it can lead to an increased risk of cancer and heavy periods.