Estradiol (E2)

What is Estradiol?

Estradiol (E2) is the primary estrogen hormone in women of reproductive age. It's produced mainly by the ovaries in women and in small amounts by the testes in men.

Why is it Important?

Estradiol is crucial for:

• Regulating menstrual cycle
• Supporting pregnancy
• Bone health and calcium metabolism
• Brain function and mood
• Cardiovascular health
• Skin and tissue health

Normal Ranges by Gender and Phase

Women (Premenopausal)

Phase	Range	Unit
Follicular Phase (Days 1-14)	30 – 120	pg/mL
Ovulation (Mid-cycle)	130 – 370	pg/mL
Luteal Phase (Days 15-28)	70 – 250	pg/mL

Other Groups

Group	Range	Unit
Men	10 – 40	pg/mL
Postmenopausal Women	0 – 30	pg/mL
Pregnant Women	Up to 20,000	pg/mL

What Do Abnormal Results Mean?

High Estradiol

In women, common causes include:

• Ovarian tumors or cysts
• Estrogen-producing tumors
• Liver disease (reduced estrogen clearance)
• Obesity (increased conversion from androgens)
• Hormone replacement therapy

In men, common causes include:

• Gynecomastia (breast tissue development)
• Testicular tumors
• Liver cirrhosis
• Obesity

Low Estradiol

In women, common causes include:

• Menopause
• Ovarian failure or insufficiency
• Polycystic ovary syndrome (PCOS)
• Anorexia or excessive exercise
• Turner syndrome
• Pituitary disorders

In men, low estradiol can affect bone density and sexual function.

When Should You Get Tested?

Estradiol may be tested if you have:

• Irregular menstrual periods
• Infertility or difficulty getting pregnant
• Menopausal symptoms (hot flashes, night sweats)
• Suspected ovarian or testicular tumors
• Monitoring hormone replacement therapy