Common misconceptions about Progesterone after Ovulation


When our founder, Amy started to suspect that she had a problem with ovulation that meant her progesterone levels weren’t rising properly after ovulation, she went to her doctor with this information and asked for a supplement. Although he was reluctant, he prescribed it for her. A couple cycles later, Amy was pregnant - and remained so - giving birth to a beautiful daughter who is now 6. But, after Amy’s experience, she discovered there was a significant lack of knowledge in women’s health surrounding low progesterone and supplementation. Many women and their doctors did not understand or believe in the power of progesterone.

Unfortunately, some misconceptions are still common today. Read on to understand more about progesterone, why it’s important and common misconceptions that could be preventing women from uncovering what could be an easy fix.   

Why is progesterone important? 

Progesterone is the hormone released after ovulation. It is required to prepare the uterus to receive an embryo, should conception have occurred and having adequate levels after ovulation is essential in this process.

What is missing, however, is the common knowledge surrounding problems with ovulation which typically manifest as progesterone deficiency. Many doctors question if low progesterone is a real diagnosis and if adding progesterone supplements can actually help.



Misconception #1: Studies show progesterone supplements don't help fix problems with ovulation.

When Amy asked her doctor for a progesterone supplement, he gave it to her - not because he thought it would work, but because taking the supplement wouldn’t harm her. This lack of faith in the effectiveness of progesterone supplements stems from a study conducted in 2016. This study followed 836 women. When a woman got a positive pregnancy test, half were given vaginal progesterone and the other half were given nothing. Live birth rates were only 2% higher in the progesterone supplement group. So, the study concluded that progesterone supplementation didn’t really help.

But this experiment was flawed. Basic biology tells us that progesterone is required to prepare the uterine lining for implantation - which is why it is released by the ovary right after ovulation. So, by the time a woman got a positive pregnancy test, the embryo had likely already implanted. Providing progesterone after confirmed pregnancy was almost “too late” - since progesterone is critically needed to prepare the uterus for conception. This study was highly publicized when it was published, so the information spread widely to doctors and women.

In 2017, another study was published. In this experiment, women were given progesterone at the start of their luteal phase (3 days after ovulation) and were able to have high levels before getting pregnant. The results of this study showed a 17% increase in  live birth rates. 

In fact, there are many studies which show progesterone supplementation starting after ovulation increased live birth rates.  Since the ovary releases progesterone right after ovulation, when supplementing, it’s important to mimic the time when the body would have released as well - which is right after ovulation, not after implantation has already occurred. 



Misconception #2: A blood test is the best and only way to confirm ovulation. 

If you suspect you have lack of ovulation or suboptimal ovulation, your doctor may order a day-21 progesterone blood test. A day-21 blood test aims to measure progesterone at the point in your cycle when it should be the highest - seven days after ovulation (given ovulation occurs on day 14). However, there are a few reasons a blood test can fall short. 

First, a day-21 blood test assumes you ovulate on day 14 of your cycle. But, every cycle is different in length, so one woman may ovulate before or after day 14. When this happens, progesterone still should be high seven days after ovulation, but that may not necessarily occur exactly on day 21. This means that you could get a negative result when in reality, your progesterone is fine. Additionally, a one point in time measure doesn’t always show the full picture. In Amy’s case, her progesterone levels would rise, then later fall. She would get a positive day-21 test, but her progesterone levels weren’t actually adequate over time. 

Second, progesterone is secreted into the blood in pulses. Studies have shown that serum progesterone levels can fluctuate eight times in the course of a single day. So, progesterone can range from 3-30 ng/ml, depending on what time of day you draw blood. This makes it extremely difficult for doctors to know if the amount of serum progesterone is actually enough to support successful conception. At 8 am, your progesterone levels could look great, but at 4 pm, they could be low. Depending on if you get the blood draw done at 8 or 4, the information provided could be giving an inaccurate picture of what is actually going on over time.  

So, what does this all mean for me? 

The most important thing for you to do is stay educated and ask your doctor the right questions. The good news is that now there is a great way to confirm successful ovulation at home so that you can understand this important piece of the fertility puzzle! 

After progesterone circulates through the blood, it is then passed into the liver where it is metabolized and secreted into urine as PdG (Pregnanediol Glucuronide). Studies have shown that PdG levels in first morning urine show an average of the serum progesterone levels from the day before. Because PdG shows an average, this makes it a better way to measure the overall progesterone production after ovulation. 

As the first at-home PdG test, Proov makes it easy to test your levels! With Proov, you can test first morning urine from days 7-10 after peak fertility - when PdG is the highest in healthy ovulatory cycles. If Proov is not positive during the testing window, you could have lack of ovulation or suboptimal ovulation, which is something to discuss with your doctor.

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