You are holding a progesterone result and the number tells you nothing, until you know which cycle day the blood was drawn. That is exactly why progesterone is so often confusing: the same value can be completely normal or strikingly low, depending on the moment.
My rule of thumb: never look at a progesterone value without the day it was taken. Below you find a clear table per cycle phase and life stage, so you can place your own result in context.
The values are in nmol/L (nanomoles per litre). Does your lab work in ng/mL? Then multiply by 3.18 (1 ng/mL = 3.18 nmol/L).
Progesterone value table per cycle phase
| Cycle phase | Rough reference (nmol/L) | What it means |
|---|---|---|
| Early follicular phase (day 1 to 7) | 0.3 to 3 | Low belongs here; no ovulation yet |
| Pre-ovulatory (day 8 to 14) | 0.3 to 5 | Starts to rise slightly around ovulation |
| Luteal phase (day 15 to 21) | 10 to 80 | Peak after a successful ovulation |
| Late luteal phase (day 22 to 28) | 5 to 60 | Falls again if there is no pregnancy |
Progesterone reference values per life stage
| Life stage | Rough reference (nmol/L) |
|---|---|
| Before puberty | less than 1 |
| Reproductive age | see cycle table above |
| Perimenopause | highly variable; lower peaks when ovulation is missed |
| After menopause | less than 2 |
| Early pregnancy (1st trimester) | 30 to 90 |
| Late pregnancy (3rd trimester) | up to around 600 |
Reference values differ per laboratory. So always keep to the range printed on your own result, and treat the numbers above as a rough compass.
Why the test day decides everything
Progesterone swings more sharply across a single cycle than almost any other hormone: from near zero in the first week to a multiple of that after ovulation. A measurement at the wrong moment therefore quickly gives a misleading picture. The usual luteal measurement is taken about seven days before your expected period, because the corpus luteum should then be at its peak.
If you have an irregular cycle, that is harder to plan. A doctor may then ask for several measurements, or to link the measurement to an ovulation test. A single luteal value of 16 nmol/L or higher can confirm that you ovulated that cycle, but says nothing about the cycle before or after. It is a snapshot, not a verdict on your fertility as a whole.
How do you read your progesterone result?
Interpretation revolves around the test moment in your cycle:
- Above 16 nmol/L in the luteal phase can confirm that you ovulated.
- Above 30 nmol/L usually points to a good, strong ovulation.
- Below 10 nmol/L in the luteal phase can fit a missed ovulation or a short luteal phase.
- A low value in the follicular phase is normal and no cause for concern.
One low luteal value says little: ovulation can shift from cycle to cycle. A value that stays low across several cycles can be more relevant and is worth discussing with a doctor.
When is an abnormal value relevant?
A low luteal progesterone value can be relevant if you:
- are trying to conceive, because a low value can make implantation harder;
- have severe PMS complaints, where the ratio between oestrogen and progesterone may play a part;
- suspect you are in perimenopause, where progesterone often falls first.
If you want to specifically check whether you ovulated, the Ovulation confirmation suits that. For the broader hormone picture, the Hormones Women panel also maps oestradiol, FSH and LH. According to NHG and Thuisarts, a single hormone value is never a diagnosis on its own, but a puzzle piece you view together with your complaints and your cycle.
Unsure whether your complaints belong to your cycle? Then read our pillar on irregular periods and which hormones to test.
Frequently asked questions
How do I convert ng/mL to nmol/L?
Multiply the value in ng/mL by 3.18. For example: 10 ng/mL equals 31.8 nmol/L. Most Dutch laboratories report in nmol/L.
Can my progesterone be normal while I still have complaints?
Yes. Complaints can also relate to the ratio between oestrogen and progesterone, or to how sensitive your body is to progesterone. The absolute value is not the whole story.
Do I need to fast for a progesterone measurement?
No, fasting is not needed. The timing in your cycle matters far more than whether you have eaten.
What if I do not know which cycle day I am on?
With an irregular or absent cycle the test day is hard to pin down. A doctor may then ask to repeat the measurement or combine it with an ovulation test, and judges the result in the light of your complaints rather than a fixed cycle day.
References
- NHG. NHG-Standaard Subfertiliteit. Dutch College of General Practitioners. Available via richtlijnen.nhg.org.
- Thuisarts.nl. Tests when a pregnancy does not happen. Dutch College of General Practitioners. Available via thuisarts.nl.
- NVOG. Information on hormone testing and the cycle. Dutch Society for Obstetrics and Gynaecology. Available via nvog.nl.
Every blood test result through Lunara includes a professional assessment by a BIG-registered doctor. For treatment decisions, discuss your results with your GP.
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