What Is a Diaphragm?

A diaphragm (DYE-uh-fram) is a small bowl made of thin, flexible silicone that’s placed in the vagina to help prevent pregnancy. It’s a type of birth control that keeps sperm from reaching an egg.

How Does a Diaphragm Work?

A diaphragm covers the cervix, the part of the uterus that opens into the vagina. It blocks semen (the fluid that holds sperm) from going into the uterus and fertilizing an egg. For added protection, another kind of birth control called spermicide is put into the bowl of the diaphragm and along its edges before it's placed deep in the vagina.

The diaphragm can be put in up to 2 hours before having sex and must be left in place at least 6 hours after sex. It should not stay in more than 24 hours. More spermicide must be used each time someone has sex while wearing the diaphragm. 

A diaphragm also needs to be cared for to work properly. After each use, it must be washed with mild soap and water, rinsed, air dried, then stored in its case. Baby powder or oil-based lubricants (like petroleum jelly) should not be put on the diaphragm to avoid damaging it. Other vaginal creams, like yeast infection medicines, also can damage it.

Someone using a diaphragm should get a new one at least every 2 years. It should be checked often for holes or weak spots and replaced as needed.

Who Is a Diaphragm Right for?

A diaphragm may be a good choice for someone who’s mature enough to get protection ready before having sex. With this kind of birth control, spermicide is always needed.

A diaphragm isn't a good choice for anyone who isn’t comfortable reaching into their vagina. And it may not be right for those with some medical conditions, such as frequent urinary tract infections. A diaphragm shouldn’t be used when someone has their period.

How Well Does a Diaphragm Prevent Pregnancy?

In 1 year, 13 out of 100 typical couples who use the diaphragm with spermicide will have an accidental pregnancy. 

How well the diaphragm works depends on:

• how well it fits
• whether a couple uses it each time they have sex
• whether spermicide is used correctly
• if it has holes or other damage

Does a Diaphragm Help Prevent STDs?

The diaphragm doesn’t protect against sexually transmitted diseases (STDs). Couples having sex must always use condoms with the diaphragm to help avoid STDs.

Abstinence (not having sex) is the only method that always prevents pregnancy and STDs.

Are There Any Problems With a Diaphragm?

Most diaphragm users have no problems with it. But possible side effects include:

• strong smells, vaginal discharge, or toxic shock syndrome (a rare but serious infection) if the diaphragm is left in too long
  
• an allergic reaction to the diaphragm or spermicide
• urinary tract infections (UTIs)
• irritation to the vagina and skin around it due to the spermicide

Where Are Diaphragms Available?

A doctor (or another health care provider) must fit a diaphragm. They'll find the right size and show how to put it in and take it out. Using a diaphragm that isn’t inserted correctly or doesn't fit well can lead to an accidental pregnancy.

If someone gains or loses weight, has been pregnant, or has sex after being fitted for a diaphragm as a virgin, the doctor should check the size again. The fit will also be checked at yearly exams.

Spermicides are sold in drugstores and some supermarkets. They're often near condoms and feminine hygiene products.

How Much Does a Diaphragm Cost?

Sometimes there's no cost for a diaphragm, but this depends on whether a person has health insurance or gets their birth control from a family planning clinic (like Planned Parenthood). Talk with your doctor to learn more.

When Should I Call the Doctor?

Someone who uses a diaphragm should call the doctor if they might be pregnant or have:

• a change in the smell or color of vaginal discharge
  
• signs of a UTI, such as burning with peeing or feeling the need to pee often
• unexplained fever or chills
• belly or pelvic pain
• pain during sex
• signs of toxic shock syndrome, such as a sunburn-like rash, achiness, fever, diarrhea, vomiting, or dizziness