Estradiol test, also known as the E2 test is done to check for proper functioning of the reproductive system in females. It is an important hormone in the female body that is responsible for the development of reproductive organs and secondary sexual characteristics in females.
During their reproductive years, women will have high amounts of estradiol, which declines with age to almost negligible at menopause.
Estradiol or E2 is the most important form of estrogens in the female body.
The other two kinds of estrogens are:
Estrone (E1): Relatively weaker form of estrogen that can be converted to another type, if the need arises.
Estriol (E3): A steroid; has the main role in pregnancy, as it helps in the growth of uterus and also with the baby’s delivery. Estriol also plays a significant role in post-menopausal women by controlling the symptoms of menopause such as dry vagina, hot flashes, insomnia, etc.
For the scope of this article, we will only discuss Estradiol, hereon:
What is the use of E2 test?
It is done to check:
- Early or delayed puberty in girls
- The proper functioning of ovaries in women and testes in men
- Follicle development in the ovaries before in vitro fertilization
- Menstrual problems (periods being very light or completely stopped) and related infertility
- Signs of breast cancer
- The possibility of ovarian cancer
- The reason for gynecomastia (overdeveloped breasts) or other female signs in men
- The cause of delayed appearance of puberty in boys
When should you do the Estradiol test?
Estradiol testing in women is recommended when you:
- Have periods that are very light or absent
- Have vaginal bleeding even after menopause
- Facing infertility
- Have hot flashes, insomnia, night sweats, or other symptoms of menopause
- Are in menopause and are taking hormone replacement therapy
- Have signs of estrogen-producing tumors
- To monitor the placenta and health of the developing baby, during pregnancy
E2 testing in men is recommended when:
There is delayed appearance of secondary sexual characteristics that are signs of puberty—growth of testicles and penis, facial and body hair, deepening of voice and development of muscle mass.
Estradiol testing details
When to get E2 test done?
Just like FSH and LH, estradiol testing is done preferably on day 3 of the menstrual cycle, although you can do it from day 2-day 4.
Sample requirement?
Estradiol test is done by inserting a small needle in your vein to draw a small amount of blood or by testing a 24-hour urine sample.
Estradiol test can also be done with a little prick on your finger with the at-home testing kit. It is available in some locations; please get in touch for more details.
How to prepare for the E2 test?
Certain medications affect the Estradiol levels in your bloodstream and you have to stop them for 3-4 weeks before doing the test for the results to be accurate. These medications include:
- Birth control pills
- Supplements like DHEA
- Hormonal medications
- Corticosteroids
- Some antibiotics such as tetracyclines
- Medication for mental disorders
Discuss your current medication with our doctor before doing the test.
How long will the results take?
It usually takes 1-2 days.
How does Estradiol work?
E2 in women is produced in ovaries, adrenal gland, and in smaller amounts in your skin, bone, brain, fat cells, and even liver. In pregnant women, it is also produced by the placenta. This hormone performs several important functions in the female body, as below:
Growth of the female reproductive system
At puberty, it is responsible for the development of reproductive organs including the vagina, the fallopian tubes, the uterus and it’s lining (the endometrium), as well as the cervical glands. It also causes the secondary sexual characteristics (breasts, pubic hair) to appear.
It also helps the growth of the muscles around the uterus, known as the myometrium.
Maintenance and release of eggs and uterine lining development
During the follicular phase of your menstrual cycle, estradiol is secreted from the follicles in the ovaries and it causes a surge in the luteinizing hormone and together they induce ovulation. After ovulation, when your cycle is in the luteal phase, Estradiol works with the hormone progesterone to build the uterine lining for implantation.
Estradiol during pregnancy
In pregnant women, estradiol is also produced by the placenta so the levels rise and it is thought to help in maintaining the pregnancy as well as helping with initiation of labor.
Bone health and estradiol
Estradiol also plays a role in your bone structure and when it starts to go down, your bone health also starts to decline. It is common for women to have osteopenia and osteoporosis after menopause, when the estradiol is low.
Brain and vascular health
Estradiol is known to have neuroprotective effects and can also help with blood flow.
Estradiol in men
While testosterone is the main sex hormone for men, they also need a balance of estradiol and testosterone to function normally. It is produced in their testes and controls the sperm production, erectile function, and the libido. It also helps with bone maintenance and brain function.
What are the normal E2 levels by age?
E2 levels not only vary with age, they also vary during every menstrual cycle.
Estradiol levels in women:
| Prepuberty | 0-20 pg/ml |
| Adolescent girls | 20–300 pg/ml |
| Menstruating women | 30–800 pg/ml |
| Pregnant women | Up to 20 000 pg/ml |
| Postmenopausal women | 0-20 pg/ml |
Estradiol levels in women during menstruation:
| Follicular phase | 20 – 200 pg/ml (maximum) |
| Just before ovulation | Upto 110 – 410 pg/ml (maximum) |
| Luteal phase | 20-160 pg/ml |
Estradiol levels in men:
| Prepuberty | 0–13 pg/ml |
| Adolescent | 0-40 pg/ml |
| Adult | 10-60 pg/ml |
What is the ideal Estradiol level for IVF?
Estradiol levels in women undergoing IVF are under 60 pg/ml at the start of the cycle. The levels start to rise as the stimulation begins and more follicles start to develop.
Estradiol can go upto 1,000 – 4,000 pg/ml over the 8-10 days of IVF stimulation.
At that point, HCG injection is given as the doctor prepares for egg retrieval in the next 34-35 hours.
What if the Estradiol low?
Low levels of E2 in women can cause:
- Delayed puberty
- Little to no development of sexual characteristics like breasts, body fat
- Disrupted or mild periods
- Depression, fatigue, mood swings can also happen as estradiol has an effect on the brain
- Weak bones and osteoporosis
- If menopausal, you can get night sweats, vaginal dryness, hot flashes
Low estradiol in men isn’t a big reason for concern, but it may cause:
- Anxiety, fatigue, depression
- Sexual dysfunction
- Loss of bone mass
- Fat accumulation
- Forgetfulness and over sleeping
What if my Estradiol is high?
Too much estradiol in women can result in:
- Acne
- Constipation
- Loss of libido and infertility
- Depression
- Weight gain
- Raised risk of developing uterine or breast cancer
- In extreme cases it can even cause a stroke, heart attack
Excessive estradiol in men can cause:
- Loss of libido and sexual function
- Development of breasts and other female characteristics
- Increased body fat
- Loss of muscle tone and thinning of facial hair
- Reduced sperm count and infertility
- Development of prostate cancer
Causes of high Estradiol
High E2 levels are indicative of the below conditions:
- Precocious puberty
- Tumors of the ovaries in women, and tumors of the testes in men
- Hyperthyroidism
- Cirrhosis of the liver
- Hormone supplements
Causes of low Estradiol levels
- Perimenopause or menopause in women (usually over 45 years)
- Premature ovarian failure
- Polycystic ovarian syndrome (PCOS)
- Excessive exercise and loss of body fat
- Eating problems such as anorexia
- Hypopituitarism
- Dysfunction of the ovaries or testes, so E2 production is affected
- Turner syndrome, a genetic disorder of females, where she has one X chromosome instead of two
- Chronic kidney disease
- Chemo or radiotherapy
For more information on Estradiol testing, and to order your at-home Estradiol test, get in touch via the form on this page. *t & c apply
Ali, E. S., Mangold, C., & Peiris, A. N. (2017). Estriol: emerging clinical benefits. Menopause (New York, N.Y.), 24(9), 1081–1085. https://doi.org/10.1097/GME.0000000000000855
Frank Z. Stanczyk, Nigel J. Clarke, Measurement of Estradiol—Challenges Ahead, The Journal of Clinical Endocrinology & Metabolism, Volume 99, Issue 1, 1 January 2014, Pages 56–58, https://doi.org/10.1210/jc.2013-2905