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A diaphragm is a shallow, bendable cup that you put inside your vagina. It covers your cervix during sex to prevent pregnancy.

What’s a diaphragm?

A diaphragm is a form of birth control that’s a shallow cup shaped like a little saucer that's made of soft silicone. You bend it in half and insert it inside your vagina to cover your cervix. 

What does a diaphragm do?

A diaphragm helps you prevent pregnancy. It works as a barrier that covers your cervix, stopping sperm from joining an egg. In order for a diaphragm to work best, it must be used with spermicide (a cream or gel that kills sperm).

How do diaphragms work with spermicide to prevent pregnancy?

Adding spermicide to your diaphragm before you put it in your vagina makes it much more effective. Spermicide has chemicals that stop sperm from moving so they can't get to an egg. The diaphragm keeps the spermicide in place, near your cervix.

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  • 83% effective

  • Costs up to $75, but can be $0

  • Prescription required

  • Put it in before sex

A diaphragm won’t protect you from STDs. Use a condom with your diaphragm to help stop pregnancy and STDs.
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