Can You Get Pregnant While Pregnant?

The human body does some pretty weird stuff, especially when you’re pregnant. But how weird is too weird? Can you get pregnant while pregnant?
We spoke with embryologist and fertility expert, Navya Muralidhar, about whether you can actually get pregnant while pregnant.

In this article: 📝

Can you get pregnant again while pregnant?

Strange as it sounds, getting pregnant with a new baby while you’re already carrying a baby is a thing.

There’s even a scientific term for it: superfetation.

If this happens, the mama is pregnant with babies who were conceived on different days.

This is different from having non-identical twins (who come from separate eggs) or from twins who are different sizes.

With superfetation, the babies have different gestational ages, and therefore different due dates.

But while some species are easily capable of superfetation, most mammals, including humans, aren’t designed that way.

Superfetation mostly happens with certain fish and some hares.

For these species, it seems to take less of a toll on their body if they have another pregnancy lined up before they’ve given birth to their first babies.

But compared to them, the human body has some practically unbeatable defensive methods to stop you from getting pregnant again if you have sex while you’re pregnant.

So, what exactly is stopping pregnancy if there’s already a little peanut in there?

1. The mucus plug is in the way

First, there’s a physical barrier. In the first few weeks of pregnancy, your mucus plug starts to form between your vagina and your uterus.

Its main job is to keep bacteria and viruses out of your baby’s current home, and it does a pretty good job of keeping out sperm cells as well.

Any deposited sperm get stuck in the thick mucus and do not go any further.

Speaking of mucus, the mucus your body produces during pregnancy is thicker and more acidic – the complete opposite of the discharge that you’ll sometimes see in the middle of your cycle.

Without the slippery ‘egg white’ cervical mucus that’s present during ovulation, it’s harder for sperm to travel or even to survive inside your body.

2. Your pregnancy hormones stop ovulation

As you might already have noticed, the balance of hormones in your body changes dramatically during early pregnancy.

Some of the main changes are a spike in your progesterone levels, and a really low level of LH (luteinizing hormone), which is essential for ovulation.

So if your question is Can you ovulate while pregnant? the answer is a pretty firm no.

And if your body doesn’t release another egg, there’s no chance you can get pregnant again.

3. Your uterus won’t let another egg implant

Once it’s fertilized, an egg needs to be able to burrow down into the lining of your uterus so that it can keep growing into a baby. This is known as implantation.

Very soon after you conceive, your body starts to build the placenta, and it stops being possible for a new egg to implant.

The bottom line? Superfetation is incredibly unlikely to happen in humans.

And even if it did happen, the babies would still be very close together in gestational age, because your body changes so quickly during early pregnancy.

So siblings born months apart, or finding out that you’re actually having two babies once you’ve already had your 12-week ultrasound? It’s not going to happen.

What are the odds of getting pregnant while pregnant?

The odds of getting pregnant while pregnant are so, so tiny.

You’re more likely to get struck by lightning on your way to cash in your winning lottery ticket during a solar eclipse on February 29th.

Human superfetation is technically possible, and there have been documented cases.

But we’re talking about 10 cases worldwide.

Considering that 385,000 babies are born in the world every single day, this really is the definition of a vanishingly small chance.

So it’s definitely not something that you need to worry about.

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Can You Get Pregnant Without Having Sex?
Can You Get Pregnant After Ovulation?
Can You Get Pregnant If You’re Not Ovulating?
Can You Get Pregnant While Breastfeeding?
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What are the Chances of Getting Pregnant from Precum?
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