How Does a Diaphragm Work?
A diaphragm keeps sperm from entering the uterus by blocking the cervix. For added protection, spermicide is put into the bowl of the diaphragm and along its edges before inserting the diaphragm high into the vagina so it covers the cervix.
The diaphragm is inserted up to 6 hours before having sex. More spermicide must be used each time a young woman has sex while wearing the diaphragm. Additional spermicide should also be used if she is going to have sex more than 3 hours after she inserted the diaphragm. After sex, the diaphragm must be left in for at least 6 hours, but no longer than 24 hours. The diaphragm can be removed by placing a finger into the vagina to pull it out.
After the diaphragm is removed, it must be washed (with mild soap and water), rinsed, and air dried, then stored in its case. It should not be dusted with baby powder and should never be used with oil-based lubricants such as mineral oil, petroleum jelly, or baby oil, which can cause the rubber to become brittle and crack. Other vaginal creams, such as yeast medicines, can also damage the rubber.
A diaphragm should be replaced at least every 2 years. It should be examined regularly for holes or weak spots, and replaced as needed.
How Well Does a Diaphragm Work?
Over the course of a year, 16 out of 100 typical couples who rely on the diaphragm with spermicide to prevent pregnancy will have an accidental pregnancy. Of course, these are average figures and the chance of getting pregnant depends on whether it's used correctly every time.
In general, how well each type of birth control method works depends on many things. With a diaphragm, some of the most important things are that it fits correctly, that it is used every time a couple has sex, and that spermicide is used appropriately.
Protection Against STDs
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.