Comparison Hormone Panel Updated May 1, 2026

Estradiol vs Progesterone

Estradiol (E2) and Progesterone (Progesterone) are two hormone lab values that can appear on the same Hormones panel and help describe related parts of blood chemistry. Both E2 and Progesterone on a lab report are measured as separate numbers, so they can be compared side by side. The key difference is that E2 reflects estradiol concentration, while Progesterone reflects progesterone concentration.

Estradiol

E2

Estradiol runs on the menstrual calendar, climbing roughly tenfold from the start of a cycle to the day before ovulation. Read without the day it was drawn, the number on your report can look alarming and mean almost nothing.

Adult Male pg/mL
10
40

Progesterone

Progesterone is the one sex-hormone test that mostly answers a yes-or-no question: did you ovulate? Drawn on the wrong day, a low number proves nothing, which is why the famous day-21 rule misfires for so many people.

Adult Male ng/mL
0.2
1.4

Estradiol (E2) and Progesterone (Progesterone) are two lab values that can appear on the same Hormones panel. Each value is reported as a separate number and reflects a different hormone concentration in blood. On a lab report, E2 vs Progesterone is a comparison of two related markers rather than one combined value. Together, they help show how hormone levels are distributed in the sample.

Two Cycle Hormones Tracked Across the Same Window

E2 measures estradiol, while Progesterone measures progesterone, so both values track different hormone molecules in the same sample. E2 and Progesterone often relate through timing, because their amounts can move in different directions across the same testing window. When E2 rises and Progesterone stays lower, the report shows a different balance than when both are elevated. That is why the difference between E2 and Progesterone is often read as a side-by-side hormone pattern on a lab report.

Estradiol Molecule vs Progesterone Molecule

Aspect Estradiol Progesterone
What it measures Estradiol concentration Progesterone concentration
Units pg/mL or pmol/L ng/mL or nmol/L
Typical adult range Varies widely; often 15–350 Varies widely; often 0.1–25
Reported as Concentration Concentration
Directly reflects Estrogen signal Luteal hormone level
Common pairing E2 on hormone panel Progesterone on hormone panel
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Reading the Estradiol-Progesterone Balance

When E2 and Progesterone are viewed together, the main value is the pattern between two hormone numbers, not a single combined score. Higher E2 with lower Progesterone can show one side of the hormone balance, while higher values for both can show a different distribution in the sample. Lower E2 and lower Progesterone together means both markers are reduced in the same report context. In each case, the comparison is about how the two numbers relate on the blood test.

Hormone and Fertility Panels That Pair the Two

E2 and Progesterone are often included on a Hormones panel, and they may also appear in fertility-focused or cycle-tracking lab bundles. The same report can list both values because the panel is meant to show hormone levels side by side. In routine lab review, seeing E2 and Progesterone together makes it easier to compare their relative balance on one page. They are not usually part of CBC, CMP, or lipid panel results, but they can be ordered alongside those panels in a broader lab set.

Estradiol vs Progesterone - Common Questions

What is the difference between E2 and Progesterone?
E2 measures estradiol concentration, while Progesterone measures progesterone concentration. Both are hormone numbers on a lab report, but they represent different molecules and are not interchangeable. The difference between E2 and Progesterone is mainly what each number tracks in the blood sample.
Which is more accurate, E2 or Progesterone?
Neither is “more accurate” in a general sense, because E2 and Progesterone measure different substances. Accuracy depends on how each assay is run and what the report is intended to show. For comparison purposes, both numbers are useful in different ways on the same Hormones panel.
Why are E2 and Progesterone tested together?
E2 and Progesterone are tested together because they give a paired view of hormone balance on the same lab report. Seeing both values side by side helps show whether one is higher, lower, or moving differently from the other. That makes the comparison more informative than either number alone.
Can E2 be high while Progesterone is low?
Yes. E2 can be higher while Progesterone is lower, and that pattern simply means the two hormone values are not rising together. On a lab report, that asymmetry describes the relationship between two separate measurements.
How are E2 and Progesterone related mathematically?
There is no single universal formula that converts E2 into Progesterone or the other way around. Some reports use an E2-to-Progesterone ratio, which is just E2 divided by Progesterone when both are in compatible units. That ratio can help compare the two numbers, but it is not a direct replacement for either value.
What units are E2 and Progesterone measured in?
E2 is commonly reported in pg/mL or pmol/L, while Progesterone is commonly reported in ng/mL or nmol/L. Units can vary by lab, so the exact format on the Hormones panel matters. Comparing E2 and Progesterone works best when the units are noted clearly on the report.
Are E2 and Progesterone part of the same panel?
They can be. E2 and Progesterone often appear together on a Hormones panel or another hormone-focused lab bundle. On the same report, they are listed as separate values rather than one combined result.
What does it mean if E2 is 150 pg/mL and Progesterone is 1.2 ng/mL?
That combination shows a higher E2 number with a relatively lower Progesterone number. On a lab report, it means the two values are not balanced at the same level, even though both are present in the same sample. The meaning comes from the comparison, not from either number alone.

Disclaimer

This content is for informational and educational purposes only. It is not intended as medical advice, diagnosis, or treatment recommendation. Reference ranges may vary by laboratory. Always discuss your results with a qualified healthcare professional.