What is an estradiol blood test?

When you’re considering getting a hormone test, estradiol is one of the hormones that may be included. But what is estradiol? Why might you need to get an estradiol blood test? Do you have to go to your doctor, or can you do this test at home?

What is estradiol?

Estradiol is one type of estrogen. This is the most potent form of estrogen, and it’s the primary form of estrogen that’s made in the female body during a woman’s reproductive years. (There are also other forms of estrogen, including estrone and estriol. The levels of these may be higher during pregnancy or after menopause.) In a woman, having too much estrogen can lead to symptoms like fatigue, low sex drive, irregular periods, and mood changes. However, having too little estrogen can actually lead to similar symptoms.

Estradiol is also the predominant estrogen found in the male body. In a man, a hormone called aromatase makes estradiol from testosterone. Estradiol actually has important functions in the male body. If a man’s levels are too high or too low, then this can cause issues. Issues like fatigue and erectile dysfunction can actually result from having too much or too little estrogen. Too much estrogen can also lead to gynecomastia, in which the male body develops breast tissue. 

How do you get an estradiol test?

The best way to test your estradiol levels is to get a blood test. While saliva testing is also a possibility, studies have not consistently shown that saliva tests for sex hormones are reliable, so blood tests are generally preferred.

To get your estradiol blood test, you can visit your doctor to ask them to order the test. Then you would need to visit a lab to have your blood drawn. For some people, this process is inconvenient. They may prefer to get a home estradiol test. You order a home test kit online and take a blood sample yourself by fingerprick. Then your results come online in a few days. 

In many cases, estradiol is tested along with levels of other hormones. This gives a complete picture of a person’s hormonal balance. Although estradiol can be tested by itself, testing it as part of a hormone panel is usually a better way to understand your hormonal health. Both men and women can benefit from having estradiol testing included in their hormone panel.

What do estradiol test results mean?

If you have low levels of estradiol, and you’re a woman, this could mean that you’re entering menopause. It’s normal for levels of estradiol to drop dramatically after menopause in women. The levels begin to decline in perimenopause, which is the period of time before menopause. If you’re a woman in your late 30s or older, and you have a low estradiol level, it’s might mean that you’re in perimenopause, or have already gone through menopause.

However, there are a variety of possible causes of high or low estrogen levels in men and women. You’ll also need to consider whether the levels of other hormones are abnormal as well, or whether it’s only estradiol that’s abnormal. This is why you should speak with a medical professional in order to interpret the results of your test.

If you get your estradiol test from a home test kit, then you’ll generally be offered a consultation with a medical professional via telemedicine in case you get any abnormal test results. This will give you a chance to discuss your situation and decide what your next steps should be. Don’t start taking any estrogen supplements or estrogen blockers without consulting with a medical professional first.

Sources

Estrogen. National Library of Medicine. https://www.ncbi.nlm.nih.gov/books/NBK538260/. Accessed 29 August 2022.

Estrogen. Cleveland Clinic. https://my.clevelandclinic.org/health/body/22353-estrogen. Accessed 29 August 2022.

Schulster M, Bernie AM. The role of estradiol in male reproductive function. Asian J Androl. 2016 May-Jun; 18(3): 435–440. doi: 10.4103/1008-682X.173932

Testosterone in human studies: Modest associations between plasma and salivary measurements. Andrologia 2018 Feb;50(1). doi:  10.1111/and.12779.