ProgesteroneFEMALE
The primary luteal-phase hormone, produced after ovulation. In men it exists at very low levels as a steroid intermediate.
The definitive confirmation that ovulation actually occurred — and central to cycle health, mood, sleep and fertility.
The plan of attack
In this order. Most people start at step four, which is why they change five things at once and learn nothing.
- Confirm the number is real
Cycle day. Progesterone is near-zero in the follicular phase and peaks about seven days after ovulation. Day 21 is only correct if your cycle is 28 days — in a 35-day cycle, day 21 is before ovulation and will read falsely low. Draw 7 days after ovulation, tracked with LH sticks — not on a fixed calendar day. - Read it with its partner
Draw 7 days after ovulation (not blindly on day 21) — track ovulation to time it correctly. Draw it alongside: Estradiol, Standard (ECLIA), LH & FSH, TSH (Thyroid-Stimulating Hormone). - Work out which direction is yours
If it's high — Normal in luteal phase and pregnancy; otherwise consider supplementation or (rarely) adrenal/ovarian pathology.
If it's low — Irregular cycles, short luteal phase, PMS-type symptoms, difficulty conceiving or maintaining early pregnancy, poor sleep. - Fix it in this order
Nutrition. Restore energy availability — under-eating and low body fat suppress ovulation, which is the actual cause of low progesterone. Adequate carbohydrate supports ovulatory function.
Lifestyle. Reduce training volume and stress if cycles are irregular — hypothalamic suppression from RED-S is very common in lean, athletic women and is fully reversible.
Supplements. Vitex (chasteberry) has modest evidence for luteal support; vitamin C, B6 and magnesium are commonly used. Discuss with a provider — Vitex affects prolactin.
Hormones. Bioidentical progesterone is prescribed for luteal support, perimenopause and in HRT — physician territory. Treat underlying thyroid or prolactin issues first.
Compounds. No peptide application. If cycles stopped on an aggressive cut or GLP-1, that's an energy-availability signal worth taking seriously.
Work down the list, not across it. Adding a compound on top of an unfixed diet is why generic protocols fail. - Retest
Mid-luteal phase across 1–2 cycles. Change one thing at a time, or the retest can't tell you which thing worked.
How to fix it
📚 ACOG guidance on abnormal uterine bleeding and ovulatory dysfunction.
🩸 Test your Progesterone
Order directly through Marek Diagnostics — no doctor's visit needed, drawn at any Quest location in the US. Code CAMERON applies 10% off automatically.
Order this test — 10% off → Browse all 102 markers →What Progesterone is usually tested alongside
On its own, one marker is a data point. These panels include Progesterone plus the markers that make it interpretable — each names every test, why it is on the list, and loads the whole set into your cart in one click at 10% off.
includes this + 10 more markers · built for women — Anywhere from late 30s onward with cycle changes, night sweats, sleep disruption, mood shifts, joint aches, brain fog, or a libido that fell off a cliff.
includes this + 9 more markers · built for women — Planning a pregnancy, actively trying, or wanting to understand your ovarian reserve before making decisions about timing.
Would you feel it? Symptoms Progesterone helps explain
People rarely search for a marker — they search for how they feel. These are the complaints where this marker is worth checking, and whether it is a first-line test or a follow-up once the obvious causes are ruled out.
Why your Progesterone might be wrong
Most abnormal results are interference, not disease. These are the things that measurably move this specific marker — check them before you change anything. Each one says whether the number is wrong and should be repeated, badly timed and should be redrawn, or real with a cause worth explaining.
Progesterone is near-zero in the follicular phase and peaks about seven days after ovulation. Day 21 is only correct if your cycle is 28 days — in a 35-day cycle, day 21 is before ovulation and will read falsely low.
Draw 7 days after ovulation, tracked with LH sticks — not on a fixed calendar day.
Secreted in pulses, so even correctly timed values vary considerably.
One low value with a confirmed LH surge is worth repeating.
What Progesterone means in combination
A single marker tells you a little. Combinations tell you the story — these are the named patterns this marker takes part in, and what each one points at.
Three completely different diagnoses that present identically, distinguished by one pairing. Low-with-low means the axis was switched off centrally — almost always energy availability. High FSH means the ovary is failing and the pituitary is shouting. A raised LH:FSH ratio with androgens points at PCOS.
Exclude pregnancy first, always. Low-with-low goes to the RED-S protocol; high FSH needs proper assessment; PCOS has its own panel. Prolactin belongs in all three workups because it is treatable.
What to test next
Markers rarely answer alone. These are the ones that put Progesterone in context — each with its own full breakdown.
Frequently asked questions
Follicular <1 ng/mL · Mid-luteal (day ~21 of a 28-day cycle) >3 ng/mL confirms ovulation, with >10 ng/mL considered robust · Postmenopausal <1 Ranges vary by laboratory and assay — always compare to the range printed on your own report.
Mid-luteal >10 ng/mL is a common target for adequate luteal function. Timing is everything — a day-21 draw is meaningless if you ovulated late.
Normal in luteal phase and pregnancy; otherwise consider supplementation or (rarely) adrenal/ovarian pathology.
Irregular cycles, short luteal phase, PMS-type symptoms, difficulty conceiving or maintaining early pregnancy, poor sleep.
You can order Progesterone directly through Marek Diagnostics without a doctor's visit — drawn at any Quest Diagnostics location in the US. Code CAMERON applies 10% off automatically.