Progesterone Levels in Pregnancy: What Do They Mean?

Progesterone levels in pregnancy are really important.

Progesterone is an essential fertility hormone that helps regulate our menstrual cycle.

In fact, it supports loads of functions all the way through pregnancy.

But is there ever too much of a good thing?

And what about a low progesterone pregnancy?

Are there any links with health issues or pregnancy loss?

If you’re asking these questions, we’ve got you.

Here’s everything you need to know about what progesterone does and what’s “normal” during pregnancy.

In this article: 📝

What does progesterone tell you in pregnancy?

Progesterone is a critical hormone in pregnancy.

In fact, the name says it all: “pro-gestation” — which literally means supporting growth and development inside the womb.

In a typical menstrual cycle, progesterone rises after ovulation (that’s the release of an egg).

It helps develop new blood vessels in the uterus and creates a perfect environment for a fertilized egg or embryo to implant.

If you don’t get pregnant, progesterone levels drop again, and your menstrual cycle starts again.

And if you do get pregnant?

Well, levels of progesterone continue rising.

This prompts the delivery of nutrients to the developing embryo.

Raised progesterone levels in pregnancy tell you everything’s lining up well for your little one.

These levels remain high throughout pregnancy, stopping your body from producing more eggs while you’re pregnant.

It’s a like your brain’s picking this cue up from progesterone, saying “Hey, we already got a fetus in, you can pause the egg-releasing process for a bit!”.

After pregnancy, progesterone also helps trigger lactation (producing and releasing milk) to help with breastfeeding.

It’s a bit of a super hormone!

What is a good level of progesterone for pregnancy?

So, what’s a normal range for progesterone levels in pregnancy?

Doctors can measure progesterone with blood tests.

It’s important to know that progesterone levels fluctuate daily, though.

So if you’re looking at your results, think of a “range” rather than precise figures.

Because it keeps rising, progesterone levels in early pregnancy (i.e., your first trimester) will also be less than in your second and third trimesters

Here’s what to expect in terms of average progesterone levels at each stage of pregnancy:

Then, after labor, your progesterone levels will start to go back to your pre-pregnancy levels by about 3 days postpartum.

Why do IVF patients take progesterone?

If you’ve started IVF or you know someone who is, you might have noticed that they take progesterone medication as part of the process.

But why?

We asked embryologist and IVF expert, Navya Muralidhar, for the deets on this one.

“During an IVF cycle, since you’re on stimulation medication from the start, your body may not produce enough progesterone when it’s time for a frozen embryo transfer.

“That’s why it’s almost always advised to take progesterone vaginal suppositories, gels or progesterone injections until your first hCG test or even until 8-10 weeks of pregnancy.

“This can avoid instances of miscarriage or pregnancy loss due to low progesterone levels.”

What is considered low progesterone levels in early pregnancy?

A low progesterone pregnancy is anything that falls significantly below the normal ranges for each trimester.

For instance, under 5 ng/mL is considered low in your first trimester.

Luckily, the vast majority of pregnant people have normal levels of progesterone.

So if everything’s feeling fine, don’t worry mama.

Low progesterone is so uncommon that doctors don’t usually test for it without a clear reason.

If you or your healthcare providers are concerned about pregnancy loss or ectopic pregnancy, they might test your progesterone levels.

Bleeding, spotting, or cramping (especially in your first trimester) are some signs they’ll look out for.

At what progesterone level could you miscarry?

At this point, medical professionals aren’t sure how low progesterone affects pregnancy.

There’s no progesterone level that definitely leads to pregnancy loss.

And high progesterone levels don’t cause problems in pregnancy.

Some experts believe a low progesterone pregnancy makes supporting a growing baby difficult and could be linked to preterm birth.

Others argue it doesn’t have any negative impacts at all.

Now, it is true that women who experience pregnancy loss will have lower progesterone levels when tested.

But, and this is important, it’s unclear whether low progesterone levels cause the loss or whether the pregnancy loss causes the drop in this hormone.

While doctors used to prescribe progesterone to prevent pregnancy loss, recent studies cast doubt on its effectiveness.

In fact, many medical studies show progesterone plays no role here.

It’s a complex topic that’s still under research, so if you’re worried about progesterone levels, chat with your medical team.

They’ll help put your mind at ease.

And if you need support along the way, your Peanut Community is here for you.