The egg and sperm can travel from their factories, meet up, and then implant into a cozy bed of tissue.

That's how pregnancy begins.

But if you don't want to get pregnant, there are a bunch of different ways to disrupt this process at basically every step along the way.

Hi, I'm Kate, and this is MinuteEarth.

One way to interrupt the pregnancy process is to stop production at the egg factory.

Even though a person has already made all the eggs they will ever make at birth, the eggs need to finish maturing in order to get released.

Certain hormones can block this final step of development, and the release of the eggs.

That's how a lot of common forms of birth control work, like birth control pills, shots, patches you put on your skin, and rings you insert.

When they're used correctly, these egg blockers are super effective, especially since they also disrupt a few other parts of the process, which we'll get to in a bit.

And if you decide later on that you do want to get pregnant, you can just stop using these forms of birth control.

The egg factory will generally start right back up.

Theoretically, you could also stop production at the sperm factory.

There are a few trials looking into pills and shots to disrupt this part of the process, but none of them have been proven effective yet.

That's likely because these factories produce so much sperm, more than a thousand little guys per second.

What has worked, though, is interrupting sperm as they make their way to fertilize the egg.

It's possible to block the path sperm travel along, like with a surgical vasectomy, which is fairly permanent, or with an external or internal condom, or a diaphragm, or sponge, which are definitely short-term.

Lots of hormonal IUDs also work by basically blocking the sperm's path.

They make the liquid the sperm swim through so thick that the tiny tadpoles can't reach the egg.

And remember those hormone-based types of birth control that stop production at the egg factory?

The hormones in those also work here to thicken that liquid.

Other birth control methods go one step farther and actually try to destroy the sperm before they fertilize the egg.

Spermicidal jelly contains chemicals that both slow sperm down and break apart their cell walls.

Though, on its own, this goo isn't super effective at preventing pregnancy.

Copper IUDs, which sperm are basically deathly allergic to, are a way longer-term, more effective way to kill sperm on their way to the egg.

You can also block the egg's path via a tubal ligation, aka getting your tubes tied.

This surgery is more than 99% effective at preventing pregnancy, though it's hard to reverse, so it's usually used by people who are sure they don't want to get pregnant anymore.

If, despite one or more of these efforts, egg and sperm do manage to meet up and fertilization occurs, a few of the forms of hormonal birth control we've talked about, including pills, shots, rings, and hormonal IUDs, have one additional way to disrupt the process.

Their hormones turn the cozy bed of tissue a fertilized egg would normally implant on into a thin, unwelcome mat that offers basically no way to stay attached.

In other words, if you don't want to get pregnant, there are a lot of different ways to interrupt the process, from production to implantation.

To learn more about the risks, effectiveness, and other benefits of specific types of birth control, check out the link below.