Home Biomarkers Estradiol (E2)

Estradiol (E2)

Fertility profile Biomarker

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Collection Type: Blood

Body System

Related System: Fertility profile

Overview

Estradiol (E2) is the primary biologically active estrogen produced mainly by the ovaries in females and in smaller amounts by the testes and peripheral tissues in males. The blood test measures circulating estradiol concentration to assess ovarian function, menstrual cycle status and estrogen exposure. It is used when evaluating infertility, irregular periods, amenorrhea, signs of early/late menopause, gynecomastia in men, or suspected estrogen‑secreting tumors. Normal values vary widely by sex, age and in women by menstrual cycle phase (follicular, ovulatory peak, luteal) and decline markedly after menopause.

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Test Preparation

Overnight fasting (8-12 hrs) is required
Do not eat or drink anything except water before the test
In females, the preferred sampling time is day 2 or 3 of the menstrual cycle for LH & FSH
For AMH: If you take hormonal birth control pills, consult your doctor as they can interfere with the results
Do not stop taking your thyroid medications on the day of the test unless otherwise advised by the doctor

Why Do I Need This Test

Which profile: Fertility profile (also used in endocrine/reproductive evaluations) - Symptoms: irregular menses, infertility, amenorrhea, hot flashes, breast changes, unexplained bleeding - Diagnoses/monitoring: ovarian reserve and function, ovulation timing, menopausal status, hormone therapy monitoring, estrogen‑secreting tumors - Reasons for abnormal levels: ovarian failure, pregnancy, PCOS, tumors, exogenous hormones, liver disease - Biological meaning: low E2 indicates hypoestrogenism/ovarian insufficiency; high E2 indicates hyperestrogenism or ovulation/pregnancy - Behaviors/lifestyle: hormone medications, obesity, alcohol/liver disease can alter levels - Family history: premature ovarian insufficiency, endocrine tumors, hereditary cancer syndromes may prompt testing

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Understanding Test Results

Values must be interpreted by cycle phase and clinical context.
Persistent values <20 pg/mL in adults usually indicate postmenopause, ovarian insufficiency or hypogonadism.
Low follicular E2 (<20–40 pg/mL) with elevated FSH suggests diminished ovarian reserve or primary ovarian failure.
Mid‑cycle rises to 150–750 pg/mL reflect normal preovulatory estrogen surge (ovulation imminent).
Sustained elevations above typical mid‑cycle ranges or very high values (>500–1,000 pg/mL) may indicate pregnancy, exogenous estrogen, estrogen‑producing ovarian tumors (e.g., granulosa cell tumor) or certain liver conditions; values >1,000 pg/mL are particularly suspicious for neoplasm.
Modestly high levels can occur with PCOS, obesity or during fertility stimulation.
Remember assays and lab reference ranges vary; correlate with symptoms, other hormones (FSH, LH, AMH), medication use and imaging when abnormal.

Normal Range

Follicular phase (women of reproductive age): 20–150 pg/mL OR 73–551 pmol/L Mid‑cycle/ovulatory peak (women): 150–750 pg/mL OR 551–2753 pmol/L Luteal phase (women): 50–250 pg/mL OR 184–918 pmol/L Postmenopausal (women): <20 pg/mL OR <73 pmol/L Men (adult): 10–40 pg/mL OR 37–147 pmol/L Prepubertal children: <10 pg/mL OR <37 pmol/L

FAQs

Q: What does estradiol E2 do?

A: Estradiol (E2) is the principal estrogen that regulates female reproductive development and function: menstrual cycle, ovulation, endometrial growth and fertility. It promotes breast development, maintains bone density, supports cardiovascular and skin health, and influences mood and libido. Produced mainly by ovaries (also placenta, adipose tissue, testes), estradiol acts through estrogen receptors to modulate gene expression in multiple tissues.

Q: What happens if E2 is high?

A: High estradiol (E2) can cause irregular or heavy menstrual bleeding, breast tenderness, bloating, mood swings and reduced fertility in women; it may raise risk of endometrial hyperplasia and hormone-sensitive cancers. In men, elevated E2 can cause gynecomastia, low libido, erectile issues and fluid retention. Causes include obesity, liver disease, hormone therapy or estrogen-producing tumors; persistent high E2 should be evaluated by a clinician.

Q: Does estradiol make you gain weight?

A: Estradiol itself does not typically cause major weight gain. It influences fat distribution, appetite and fluid balance, so some people notice increased water retention or shifts in fat to hips and thighs. During menopause, falling estradiol is linked to weight gain; replacing estradiol can reduce central fat accumulation for some. Individual response varies with dose, route, age, diet and activity.

Q: What if the E2 level is low?

A: If estradiol (E2) is low, you may have irregular or absent periods, hot flashes, vaginal dryness, low libido, mood changes and higher risk of bone loss and infertility. Causes include menopause, ovarian insufficiency, hypogonadism, certain medications or extreme exercise/low weight. A clinician can evaluate with tests and recommend treatments such as hormone therapy, fertility options and bone‑protective measures (calcium, vitamin D, weight‑bearing exercise).

Q: What is a normal estradiol E2 level for a woman?

A: Normal estradiol (E2) varies with cycle stage and menopause. Typical ranges: follicular phase about 20–150 pg/mL (70–550 pmol/L); mid‑cycle (ovulatory) peak about 150–750 pg/mL (550–2,750 pmol/L); luteal phase about 70–350 pg/mL (250–1,280 pmol/L); postmenopausal usually <30 pg/mL (<110 pmol/L). Values vary by lab method and age, so discuss results with your clinician.

Q: What does E2 do in the body?

A: E2 (estradiol) is a primary estrogen that regulates female reproductive development and the menstrual cycle, supports ovulation and fertility, and maintains vaginal and uterine tissues. It preserves bone density, influences fat distribution and cholesterol levels, affects mood, cognition, skin and libido, and contributes to cardiovascular and vascular function. In both sexes it modulates bone and brain health.