The Calming Hormone
Progesterone is the "pro-gestation" hormone—it prepares the uterine lining for pregnancy. But it's also nature's Valium: it converts to allopregnanolone, which calms GABA receptors in your brain. It counterbalances estrogen's growth signals, supports sleep, and has anti-inflammatory effects.
What is Progesterone?
Progesterone is produced by the corpus luteum after ovulation and by the placenta during pregnancy. Levels are very low in the follicular phase and rise dramatically post-ovulation. Mid-luteal progesterone >3 ng/mL confirms ovulation occurred.
↑ What High Progesterone Means
Normal in the second half of the cycle and pregnancy. Abnormally high outside these contexts can indicate ovarian cysts or supplementation effects.
Common symptoms:
Drowsiness and fatigue · Bloating · Breast tenderness · Normal in pregnancy
↓ What Low Progesterone Means
Anovulatory cycles, luteal phase defect, or menopause. Low progesterone relative to estrogen ("estrogen dominance") causes PMS, heavy periods, breast tenderness, anxiety, and insomnia.
Common symptoms:
PMS: mood swings, irritability, anxiety · Insomnia (especially premenstrual) · Heavy or irregular periods · Breast tenderness · Spotting before period · Difficulty maintaining pregnancy · Bloating
Why It Matters
When normal:
Prepares uterine lining for pregnancy
Natural anxiolytic via GABA modulation
Counterbalances estrogen
Supports sleep
Anti-inflammatory
Bone-building support
Risks if abnormal:
Low: infertility, miscarriage, PMS, estrogen dominance, insomnia
Low ratio to estrogen: heavy periods, endometrial hyperplasia, fibroids
What Can Cause Abnormal Levels?
Anovulation (low)
55% likelyNo ovulation = no corpus luteum = no progesterone. Common in PCOS, stress, perimenopause.
Perimenopause/Menopause (low)
50% likelyProgesterone drops before estrogen in the menopause transition.
Chronic Stress
Cortisol competes with progesterone for precursors ("cortisol steal").
Luteal Phase Defect
Corpus luteum doesn't produce enough progesterone for long enough.
Hypothyroidism
Thyroid dysfunction impairs ovulation and progesterone production.
What You Can Do
Stress management: sleep, meditation, boundaries
Impact: Reduces cortisol competition \u00B7 Timeline: 4-8 weeks
Adequate caloric intake and body fat
Impact: Undernutrition suppresses ovulation \u00B7 Timeline: 4-8 weeks
If lifestyle changes aren't enough:
Vitex (chasteberry): 20-40mg daily
Impact: Best-studied herbal for luteal progesterone support \u00B7 Timeline: 2-3 cycles
Vitamin B6: 50-100mg daily
Impact: Supports corpus luteum function \u00B7 Timeline: 2-3 cycles
Vitamin C: 750mg daily in luteal phase
Impact: Studies show increased progesterone levels \u00B7 Timeline: 1-2 cycles
Recommended retest: Day 21 of cycle (7 days post-ovulation); repeat 2-3 cycles
Related Markers
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