A crash course on PdG and progesterone and why they matter!


By Amy Beckley, PhD, Proov founder, inventor, and CEO

You may have heard of progesterone before, but PdG may not sound as familiar.  So, what is it? PdG (Pregnanediol) is the urine metabolite of progesterone; progesterone rises after ovulation and gets broken down into PdG in the liver, eventually coming out in your urine. If you don’t ovulate, your body won’t produce any progesterone, and therefore no PdG. Testing for the PdG in urine can be an easy, painless way to see if you’ve successfully ovulated. Let’s dive in to find out more about why this matters.

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Successful ovulation is needed to successfully conceive.  

Did you know that problems with ovulation are the leading cause of female infertility? If you aren’t ovulating regularly, it will be difficult to conceive. Symptoms of irregular or absence of ovulation include the cessation of menstruation (amenorrhea) or periods of irregular lengths (oligomenorrhea). 

Regular ovulation is a sign of good health and well-being.  

In fact, the American College of Obstetrics and Gynecology (ACOG) considers your period and menstrual cycle to be critical indicators of overall female health.  

Tracking PdG over multiple days can confirm if ovulation happened.

Other ovulation confirmation methods include basal body temperature (BBT) tracking and blood progesterone testing. While BBT can be helpful at providing a sign that ovulation has happened, this method of can be impacted by sickness, alcohol consumption, or a toasty toddler sharing a bed.  

The slight increase in temperature that occurs after ovulation is actually induced and regulated by the increase in progesterone that occurs after ovulation. After an egg leaves an ovarian follicle, the follicle transforms into a corpus luteum. The corpus luteum is a progesterone producing factory that is important for maintaining the endometrial lining of the uterus, which is required to support a healthy pregnancy.

PdG, on the other hand, is the urine metabolite of progesterone. Published studies have shown that tracking PdG over multiple days—seven to ten days after suspected ovulation—can confirm successful ovulation, meaning that ovulation was healthy and provided the best chance at possible conception that cycle.  

Confirming ovulation can complete the ovulation puzzle. 

Equally important when it comes to conceiving is accurately predicting ovulation. This is important so that a couple knows when fertility is at its highest, and they can time intercourse appropriately. Natalist offers accurate and accessible ovulation tests that predict ovulation by tracking luteinizing hormone, or LH for short. By starting PdG testing seven days after a positive Natalist ovulation test and testing every day through day ten, a woman can complete the ovulation puzzle by confirming that successful ovulation has, in fact, occurred—and both pieces are critical to moving you forward in your trying-to-conceive journey!  

Sounds great!  How do I test for PdG?

Enter Proov! Proov is the first and only FDA-cleared test that measures PdG over multiple days to confirm successful ovulation. If healthy ovulation has occurred, PdG levels rise in the second half of the cycle, or luteal phase, after suspected ovulation. Proov works by measuring PdG, the urine metabolite of progesterone, on days seven, eight, nine, and ten after suspected ovulation. If a woman gets positives during this window, then great—she can feel confident that she successfully ovulated that cycle!  

Regardless of results, Proov provides powerful information that can help couples move forward by either ruling out or detecting ovulatory problems that might make it more difficult to conceive.  

Tell me more about how Proov and Natalist are a great pair!

Proov works best when used in conjunction with ovulation tests that measure LH. Natalist has awesome, accurate, and easy-to-use ovulation tests that can help a woman determine her peak fertility. Then, after Prooving, a woman can understand if she’s successfully conceived with Natalist pregnancy tests.  

Healthy ovulation is so important when it comes to trying to conceive. With Natalist and Proov, you can see the full ovulation picture and be empowered with more valuable information sooner.