ELI5: Explain Like I'm 5

Implantation bleeding

Implantation bleeding refers to a tiny bit of blood that some women experience during early pregnancy when a fertilized egg is implanting itself into the lining of the uterus.

Imagine that when you were in your mom's belly, your body started off as a tiny, little cell. But as you grew bigger and bigger, that cell found a nice cozy place to snuggle in inside your mom's tummy. That cozy place is called the uterus, which is a special place where babies grow.

Well, when a woman gets pregnant, a tiny cell (called an embryo) grows in her uterus until it's big enough to turn into a baby. But when the embryo is first getting ready to “snuggle in,” it can cause a little bit of spotting or bleeding as it attaches to the uterus lining.

The spotting is usually light and only lasts a day or two. It's really important to remember that this is normal and nothing to worry about. It doesn't mean that the baby is in danger — in fact, it's a sign that everything is going well and that the baby is growing just like it should.

So, think of implantation bleeding like a little bit of paint that got left behind as you were being painted inside your mom's belly. It's no big deal and your mommy doesn't need to worry!