Do Babies Poop in the Womb?

You know you’re going to have more than enough pee and poop to deal with once your baby is here, but what happens before they’re born?

And, do babies poop in the womb?

Let's find out together.

In this article: 📝

How do babies poop in the womb?

Your baby doesn’t worry about mealtimes when they’re still in the womb.

And they can’t truly pee or poop until their digestive system has actual food (or, to begin with, milk) to deal with.

But they still have waste products from their bodily functions, so they rely on the placenta and umbilical cord to give them what they need, and get rid of what they don’t.

As your baby grows, their waste-filled blood is exchanged with your clean blood, and your liver works overtime to clean everything again.

Did we mention you’re a superhero, mama?

And, even though babies aren’t really pooping while they’re in the womb, something is forming in their digestive system – sludgy, sticky, dark meconium.

What is meconium?

Meconium is a mix of old cells, mucus, bile, water, and lanugo (which is the downy hair that babies grow to keep warm, and then mostly lose before they’re born).

By 40 weeks of pregnancy, babies will have built up about 200g of meconium – about as much as a small pot of yogurt.

It’s supposed to stay in their bodies until after birth, and then it comes out in their first few dirty diapers.

But just because a baby isn’t supposed to do something, doesn’t mean they won’t, and the same goes for pooping in the womb.

How common is it for a baby to poop in the womb?

Babies sometimes poop while they’re still in the womb – usually while their mama is in labor.

In fact, between 12% and 20% of babies poop out some meconium before they’re born.

The number increases the further they go past their due date.

Why do babies poop in the womb? We’re not completely sure, but it’s much more likely to happen if they become stressed.

If the placenta isn’t working as well as it could, if there’s a problem with the umbilical cord, or if labor goes on for a long time, it increases the chances of a baby passing meconium before birth.

It’s important to know the signs that a baby has pooped in the womb, because, while most babies who do will be completely fine, it can mean that they need some special care in the first week after they’re born.

The first sign is usually seeing meconium when your water breaks.

The fluid should be clear or straw-colored. If there are green or brown streaks, or if there are lumps, it’s probably meconium.

If you see any of this, head straight to the hospital, even if you haven’t had contractions yet, so that you and your baby can be monitored.

What happens if a baby poops in the womb?

Usually, if your baby does poop, they’ll be watched closely while you’re in labor for signs of distress, such as their heart rate dropping during contractions.

Your medical team will decide what to do based on those numbers and discuss your options with you – it might mean that your baby has to be delivered more quickly (for example, by c-section) – but it doesn’t have to.

Right after they’re born, your baby might need to have fluid suctioned out of their mouth and nose.

They’ll also be checked regularly by a doctor in the first hours of their life (NICE guidelines are to check their vitals every 2 hours for the first 12 hours).

Between 4% and 10% of the babies who poop in the womb breathe some meconium into their lungs, which is a more serious problem.

It’s known as meconium aspiration syndrome or MAS.

Babies with MAS will usually need a short stay in the NICU or special care unit.

They might need oxygen or a chest x-ray, and they’ll be monitored for signs of pneumonia and other infections.

Although MAS can be very dangerous if it’s not treated quickly, most babies do make a full recovery.

So, there you have it!

And if you're looking for more support from other mamas who've been through it all, that's where our Community can help.

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