Why You Should Care About Progesterone and what is progesterones function?

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


If you went through high school sex ed, you’re probably familiar with estrogen. 

However, you may be less familiar with the yin to estrogen’s yang: progesterone. Keep reading to learn more about progesterone and why you should care about it!


What is progesterone?

Progesterone is one of the two main female reproductive hormones, along with estrogen. It rises after ovulation during the second half of your cycle, also known as the luteal phase. 

Progesterone’s main job is to control the cycle and aid in reproduction. However, it also plays roles in brain function, bone health, energy, and mood. It’s a powerful hormone!

Why should I care about progesterone?

In the female reproductive system, progesterone helps regulate the cycle and aids in conception. After ovulation occurs, the ovary starts producing progesterone. 

Progesterone prepares the uterus for implantation and conception by making the uterine lining “sticky” enough to allow a fertilized embryo to comfortably implant. Progesterone levels need to be elevated during the “implantation window” which is the few days during your cycle in which an embryo can attach to the uterine wall. 

Without enough progesterone for long enough during the implantation window, it can be more difficult to get pregnant. In fact, low progesterone levels after ovulation is the #1 cause of female infertility — but also one of the easiest to solve, so don’t worry!

If you do conceive that cycle, the ovary should continue producing progesterone during early pregnancy. Once the pregnancy is far enough along, the placenta will take over progesterone production for the rest of pregnancy.

During pregnancy, progesterone helps foster a healthy uterine environment, bringing oxygen and essential nutrients to the growing baby. Progesterone also prevents preterm contractions.

Now, you may be thinking, That’s great and all but I’m not trying to conceive. And we hear you! Progesterone plays various roles in our overall health as well.

Studies show progesterone stimulates bone formation to help keep our bones strong throughout our lives. It also may impact our brain function, especially as we get closer to menopause.

Finally, the studies show estrogen-progesterone balance can affect our mood. Low progesterone levels before our periods (during that critical implantation window) can cause mood swings, depressive episodes, and PMS.


How do I measure progesterone?

There are two main ways to measure progesterone: via blood or via urine. Progesterone blood tests directly measure levels in blood, while urine-based PdG tests measure a marker of progesterone found in urine.


Progesterone blood tests require a visit to a lab or your doctor. They’re most commonly performed on cycle day 21, about 7 days after ovulation when progesterone should start reaching the optimal level.

The one issue with blood tests, however, is they only show levels at that one point in time. This can be problematic since, as we know, progesterone needs to remain elevated for the entire implantation window for a healthy cycle and the best possible chance at pregnancy.

Measuring levels on cycle day 21 may not give you enough insight into your levels across the implantation window, especially if you’re trying to conceive. 

This is where PdG tests come in! Since PdG tests are urine-based, you can non-invasively track levels over several days, specifically the all-important implantation window. Studies show PdG levels in first morning urine correlate to an average of all serum progesterone levels from the previous day.

Proov Confirm PdG tests are the first and only FDA cleared PdG test kit to confirm ovulation quality at home. The patented Proov PdG testing protocol recommends testing on days 7-10 past your first positive ovulation tests to ensure healthy levels during the implantation window. 

What do I do if my progesterone levels are low?

If you get a few negative Proov PdG tests during the implantation window or a blood test shows your progesterone levels may be lower than ideal, there’s no need to panic! There are plenty of ways to naturally raise your levels. Here are some of our favorites:


Seed cycling

Seed cycling involves eating certain seeds during certain phases of your cycle to promote overall hormone balance. Pumpkin and flax seeds during the first half of your cycle promotes healthy estrogen production, while eating sunflower and sesame seeds during the second half of your cycle promotes progesterone production. We recommend the Funk It Seed Cycling kit to make achieving hormone balance as easy as possible!

Diet and lifestyle changes

While our food doesn’t directly contain progesterone, there are a few foods that may promote progesterone production, including beans, broccoli, spinach, kale, pumpkin, and nuts, among others. Additionally, eating a well balanced diet filled with complex carbohydrates, protein, and healthy fats can help support hormone health.


Reduce stress

We know — reducing stress is easier said than done. However, our cortisol (stress hormone) levels can directly impact our reproductive hormones.


When we’re under a lot of stress — whether that be from excessive exercise, work, or other factors — our body produces more cortisol to combat the effects of stress. Elevated cortisol tells our body that it’s probably not the best time to reproduce, so it inhibits ovary function and reproductive hormone production, i.e. progesterone. 


In fact, studies have shown that elevated cortisol levels are associated with lack of ovulation and progesterone production. If you have an activity that helps you reduce stress, we recommend making it a regular practice in your daily life. 


Prescription medications

If your progesterone deficiency is more pronounced or natural methods aren’t working, you may want to talk to your doctor about prescription progesterone medications. These must be prescribed by a doctor, so we definitely recommend visiting yours if this is something you may be interested in. 


The more you know about your hormones, the better you can help keep them in balance!