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It's really important to use a diaphragm correctly — every time you have sex. Here's how you can get maximum pregnancy prevention from your diaphragm.

How effective are diaphragms?

Here’s the deal on diaphragm effectiveness: If you use your diaphragm perfectly every single time you have sex, it’s 94% effective. But nobody’s perfect, so in real life diaphragms are about 83% effective — that means about 13 out of 100 people who use a diaphragm will get pregnant each year. That's because people don't always follow the directions correctly, or they don't use their diaphragm every single time they have sex.

Want an even more effective form of birth control? Check out the IUD and the implant.  They’re the most effective kinds of birth control.

How can I make my diaphragm more effective?

There are a few ways to supercharge your pregnancy protection with your diaphragm:

  • Use your diaphragm EVERY SINGLE TIME you have vaginal sex.

  • Use spermicide with your diaphragm.

  • Put your diaphragm in before you start having sex, even before you’re aroused if possible.

  • Make sure your diaphragm is covering your cervix. (Learn how to use a diaphragm.)

  • Use another method of birth control along with your diaphragm. Your partner can pull out before ejaculating (withdrawal), or wear a condom. Bonus: Condoms also help protect you and your partner from sexually transmitted infections.

Do diaphragms protect against STDs?

Diaphragms don’t protect against sexually transmitted infections — but luckily, condoms do. If you have vaginal, anal, or oral sex, using condoms every time (plus getting tested regularly for STDs) is the best way to stay healthy.

More questions from patients:

How effective is a diaphragm if you use it with spermicide?

A diaphragm is 88% effective when you use it with spermicide (a cream or gel that kills sperm). So it's really important to use a diaphragm with spermicide — every time you have sex.

How much spermicide should I use with my diaphragm?

Before putting your diaphragm in, fill the diaphragm's bowl with about 1 tablespoon (a big scoop) of spermicide. Then,  spread a thin layer of spermicide around the rim of the diaphragm with your finger. 

After putting your diaphragm in, add more spermicide inside your vagina before you have sex. If your diaphragm comes out or shifts during sex, add more spermicide before you adjust or put your diaphragm back in.  

Always follow the instructions on the package your diaphragm came in.

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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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