What is a progesterone metabolite test?

Written by:, PhD, Founder and Inventor of the Proov test — the first and only FDA-cleared test to confirm successful ovulation at home.

Written by: Dr. Amy Beckley, PhD, Founder and Inventor of the Proov test the first and only FDA-cleared test to confirm successful ovulation at home.

Written on 12/19/21

what is a progesterone metabolite test

While you may have heard of a progesterone test, have you ever heard of a progesterone metabolite test?

Here at Proov, hormone tests are our bread and butter. But, we know not everyone is well-versed in the world of hormone testing and, sometimes, it can be downright confusing!

But that’s okay — our job is to help you navigate this new world, and that starts with explaining new terms. While you may have heard of a progesterone test, have you ever heard of a progesterone metabolite test?

We invented Proov Confirm, the first and only FDA cleared progesterone metabolite test to check for successful ovulation, so it’s only fitting that we tell you a little about it! Keep reading to learn more.

What is progesterone?

As one of the two main female sex hormones, progesterone helps regulate your cycle. It’s main job is to prepare your uterine lining for implantation and pregnancy, by making it “sticky” enough so that an embryo could implant comfortably.

Progesterone production takes off during the second half of your cycle (the luteal phase) after ovulation occurs. Its presence confirms that ovulation occurred. Progesterone is necessary for supporting implantation and the best chance of pregnancy.

If you do successfully conceive, progesterone remains elevated during pregnancy to support the health of the uterine lining and the growing baby. It provides oxygen and essential nutrients, and prevents premature contractions.

Not only does progesterone play a huge role in our reproductive health, but its benefits stretch far beyond reproduction. Progesterone levels are essential for balancing out estrogen and preventing estrogen dominance.

Progesterone also promotes brain function, healthy bones, supports breast health, and calms PMS symptoms.

What is a progesterone metabolite?

Progesterone circulates through our blood. Once it has made its way through our system and has done its job, our body produces more progesterone. This means the old progesterone is no longer needed and we need to get rid of it.

To do this, our body breaks progesterone down into a form in which it can be excreted. When something in our body gets broken down, it gets “metabolized” into a “metabolite”. (We prefer “marker” as a more approachable term.)

Progesterone passes through our blood and to our liver, which metabolizes progesterone each night when we sleep into its metabolite, Pregnanediol Glucuronide (PdG for short). Then, it’s ready to leave the body in our urine when we use the bathroom first thing the next morning.

Scientists have been studying PdG since 1949. Studies have shown that PdG levels in first morning urine correlate to an average of all progesterone levels from the previous day.

Additionally, studies show progesterone levels can fluctuate drastically — day by day, and even hour by hour! — making a single blood test nondiagnostic. PdG, on the other hand, isn’t subject to the same drastic fluctuations, meaning PdG levels show an overall average (versus a single point in time) and can offer a more complete picture.

Therefore, scientists considered PdG to be a good clinical marker of luteal activity, except that there was no device to measure it outside of a laboratory. And that’s where Proov comes in — but we’re getting ahead of ourselves.

what is a progesterone metabolite test

Scientists considered PdG to be a good clinical marker of luteal activity, except that there was no device to measure it outside of a laboratory.

Why should I use a PdG test?

There are two main reasons why you’d want to use a PdG test:

  1. To confirm ovulation
  2. To confirm succssful ovulation, meaning PdG levels remained elevated during critical days (i.e. the implantation window) to allow for a higher chance chance at pregnancy.

Now, you may be thinking, Wait, doesn’t an ovulation test confirm ovulation? In fact, it doesn’t!

Ovulation tests measure luteinizing hormone, which surges about 12-36 hours before ovulation and triggers it to occur. A positive ovulation test predicts that ovulation should occur soon, but doesn’t tell you whether or not it actually happened.

PdG, on the other hand, is only produced after ovulation occurs. Therefore, a presence of PdG confirms that ovulation did in fact occur.

While you can also confirm ovulation with something like a progesterone blood test or basal body temperature (BBT) tracking, these two methods only confirm whether or not an egg was released. They fall short of confirming the overall "success" of your ovulation.

Successful ovulation refers to whether or not an egg was released and whether or not progesterone or PdG levels remained elevated for long enough to allow for a higher chance at pregnancy. As we know, progesterone (and therefore PdG) is essential for supporting successful implantation and conception.

In fact, studies show that elevated PdG levels during the luteal phase correlates to a 92% chance at successful pregnancy, compared to only a 19% chance in those with low PdG levels. Confirming ovulation with a different method wouldn’t give you the powerful insight into successful ovulation that PdG tests can.

Additionally, compared to a traditional blood test, a PdG test offers a non-invasive way to confirm ovulation. Rather than getting poked with a needle, all you need to do is pee!

what is a progesterone metabolite test

Proov Confirm is the first and only FDA cleared PdG test to check for successful ovulation at home.

When do I take a PdG test?

Since PdG should be elevated during the implantation window, it only makes sense that’s when you should test! The implantation window typically lasts from days 7-10 past peak fertility, with the most common day of implantation being day 9 past peak.

If you’re following the patented Proov PdG testing protocol, that’s exactly when you’ll test. We recommend downloading the free Proov Insight app for reminders when to test exactly on the Proov protocol.

But, we’re getting ahead of ourselves! First, you’ll want to take a PdG test at the beginning of your cycle on cycle day 5 or the day after your period ends — whichever comes later. This is called your baseline.

Your baseline test will be negative, but don’t forget it! It’s important for comparing to PdG results later in your cycle.

From there, you’ll want to track peak fertility using the method of your choice. We typically recommend ovulation tests (especially Proov Predict!). Your first positive ovulation test is considered “peak fertility” and, after it, there’s no need to continue testing.

Your first positive ovulation test is also 0 days past peak (0 DPP). You’ll then count out 7 days and test with Proov Confirm PdG tests daily on days 7-10 past peak fertility. Be sure to always use first morning urine and scan your result into the Proov Insight app at exactly 10 minutes after dip!

What does a positive PdG test mean?

While a single positive Proov PdG test confirms ovulation, we like to see 3-4 positive results during the implantation window to ensure PdG levels are elevated for long enough to allow for a higher chance at pregnancy. You’d also want to ensure you get a positive result on 10 DPP to ensure your levels aren’t dropping too early.

Three or four positive PdG results (with a positive on 10 DPP) indicates a successful ovulation, which allows for the best chance at successful pregnancy.

Testing the main progesterone metabolite, PdG, can provide powerful insight into your ovulation health and chances at conception!

BACK TO TOP