What Is a Diaphragm?

A diaphragm is a dome-shaped bowl made of thin, flexible silicone that sits over the cervix, the part of the uterus that opens into the vagina. It covers the cervix so sperm can't get in and fertilize an egg.

How Does a Diaphragm Work?

A diaphragm keeps sperm from entering the uterus by covering the cervix. For added protection, spermicide is put into the bowl of the diaphragm and along its edges before it's inserted. The diaphragm is placed high into the vagina so it covers the cervix.

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. The diaphragm should not stay in longer than 24 hours. More spermicide must be used each time a young woman has sex while wearing the diaphragm. 

How Well Does a Diaphragm Work?

Over the course of a year, 12 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 every time they have sex
• whether spermicide is used appropriately

A diaphragm also needs to be cared for. After each use, it must be washed (with mild soap and water), rinsed, and air dried, then stored in its case. Don't put baby powder or oil-based lubricants (such as mineral oil, petroleum jelly, or baby oil) on the diaphragm. Other vaginal creams, such as yeast infection medicines, also can damage the diaphragm.

A diaphragm should be replaced at least every 2 years. Check it regularly for holes or weak spots, and replace as needed.

Does a Diaphragm Help Prevent STDs?

No. The diaphragm does not protect against STDs. Couples having sex must always use condoms along with the diaphragm to protect against STDs.

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

Are There Any Problems With a Diaphragm?

Most young women who use a diaphragm have no problems with it. But possible side effects include:

• from the spermicide, irritation of the vagina and surrounding skin or an allergic reaction
• strong odors or vaginal discharge if the diaphragm is left in too long
• an allergic raction to the material in the diaphragm (this is rare)
• a higher risk for urinary tract infections (UTIs)
• toxic shock syndrome if the diaphragm is left in too long (this is rare)

Who Is a Diaphragm Right for?

A diaphragm may be a good option for a young woman who can take responsibility for protection before having sex. With a diaphragm, she must always have a supply of spermicide.

The diaphragm isn't a good choice for anyone who is uncomfortable or uneasy with the thought of reaching into her vagina. And it may not be right for those with some medical conditions, such as frequent urinary tract infections. The diaphragm should not be used when a young woman has her period.

Where Are Diaphragms Available?

A doctor or nurse practitioner must fit a girl for a diaphragm. During a pelvic exam, the doctor or NP will find the right size diaphragm and teach her how to insert and remove it. A diaphragm that's inserted incorrectly or doesn't fit well can lead to pregnancy.

During an annual exam, the doctor or nurse will make sure the diaphragm still fits correctly. It may not fit if a girl has gained or lost weight, had a baby, had an abortion, or was fitted when she was a virgin and she is now having sex. A woman who has had any of these changes should have her doctor check the fit of the diaphragm right away rather than wait until her annual exam.

How Much Does a Diaphragm Cost?

Costs can range from $0 to about $250 for the diaphragm and the office visit. Many health insurance plans cover the costs, and family planning clinics (such as Planned Parenthood) may charge less. Also, the cost of spermicide is about $0.50 to $1.50 per use.

A diaphragm should be replaced every 2 years.

When Should I Call the Doctor?

If you use a diaphragm, call the doctor if you:

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