Heavy, painful periods. Severe PMS. Breast tenderness. Mood swings that derail your entire week. If these symptoms rule your monthly cycle, you may be dealing with estrogen dominance - a hormone imbalance where estrogen's effects overpower progesterone's.
What Is Estrogen Dominance?
Estrogen dominance isn't always about having too much estrogen. It's about the ratio between estrogen and progesterone being off. This can happen in several ways:
- High estrogen + normal progesterone: True estrogen excess
- Normal estrogen + low progesterone: Relative estrogen dominance (most common)
- High estrogen + low progesterone: The worst of both worlds
In a healthy cycle, estrogen and progesterone work together in balance. Estrogen is dominant in the first half of your cycle (follicular phase), building the uterine lining. After ovulation, progesterone rises and balances estrogen in the second half (luteal phase).
When this balance is disrupted, estrogen's effects go unchecked.
Symptoms of Estrogen Dominance
- Heavy periods - soaking through pads/tampons, clotting
- Painful periods - severe cramping
- Severe PMS - mood swings, irritability, anxiety
- Breast tenderness and swelling
- Bloating and water retention
- Weight gain, especially hips and thighs
- Headaches or migraines, often around menstruation
- Fibrocystic breasts
- Uterine fibroids
- Endometriosis
- Irregular cycles
- Low libido
- Fatigue
What Causes Estrogen Dominance?
Low Progesterone
This is the most common cause. Progesterone is only produced after ovulation, so if you're not ovulating regularly (common with stress, PCOS, or perimenopause), progesterone will be low.
Excess Body Fat
Fat tissue produces estrogen through an enzyme called aromatase. More body fat = more estrogen production.
Poor Estrogen Metabolism
Your liver processes and eliminates estrogen. If liver function is impaired or you have certain genetic variants (COMT, CYP1B1), estrogen may not be cleared efficiently.
Chronic Stress
Stress causes your body to prioritize cortisol production over progesterone (they share the same precursor). This is sometimes called "pregnenolone steal."
Environmental Estrogens (Xenoestrogens)
Chemicals in plastics, pesticides, personal care products, and more can mimic estrogen in your body.
Birth Control
Synthetic estrogens in hormonal contraceptives can contribute to estrogen dominance, especially when discontinued.
Important: Estrogen dominance is often a symptom of an underlying issue - stress, anovulation, liver function, or inflammation - not just a hormone problem to "fix" in isolation.
Testing for Estrogen Dominance
The Critical Factor: Timing
Hormone levels change dramatically throughout your cycle. For the most accurate picture:
- Test on day 19-22 of your cycle (about 5-7 days after ovulation)
- This is when progesterone should be at its peak
- If your cycles are irregular, work with a provider to determine timing
Key Markers to Test
- Estradiol (E2): The primary estrogen
- Progesterone: Should be elevated mid-luteal phase (ideally above 10-15 ng/mL)
- Progesterone-to-Estradiol Ratio: Some practitioners look at the ratio rather than absolute values
Additional Helpful Tests
- DHEA-S: Adrenal health marker
- Cortisol: Chronic stress assessment
- Thyroid panel: Thyroid and estrogen metabolism are connected
- Liver enzymes: Liver health affects estrogen clearance
Addressing Estrogen Dominance
Support Ovulation
If low progesterone is the issue, the root cause is often anovulation. Addressing blood sugar, stress, and thyroid function can help restore regular ovulation.
Support Estrogen Metabolism
- Cruciferous vegetables: Broccoli, cauliflower, Brussels sprouts contain compounds that support healthy estrogen metabolism
- Fiber: Helps eliminate estrogen through the digestive tract
- Limit alcohol: Alcohol impairs estrogen metabolism in the liver
- Reduce environmental estrogens: Choose glass over plastic, check personal care products
Manage Stress
Chronic stress directly suppresses progesterone. Stress management isn't optional - it's essential for hormone balance.
Maintain Healthy Body Composition
Reducing excess body fat can lower estrogen production from adipose tissue.
The Bottom Line
If your periods are making your life miserable, estrogen dominance may be the culprit. But testing at the right time of your cycle is crucial - random hormone tests often miss the problem entirely.
Understanding your estrogen-to-progesterone balance gives you actionable information to address the root cause, not just mask symptoms.
Ready to understand your hormone balance? Get your estrogen and progesterone tested at the right time in your cycle with EllaDx.