Barrier methods to prevent pregnancy, such as condoms or cervical caps, have been around for centuries. The cervical cap covers the cervix and prevents semen from entering the uterus. A version of the cervical cap has been used since the late 1800s.

The FDA approved the modern-day cervical cap in 1988. Various brands have been available since then. Currently, FemCap is the only cervical cap available in the United States.

The cervical cap is a reusable dome-shaped cap made from nonallergenic silicone rubber that is inserted into the vagina.

The cervical cap is similar to the diaphragm. The only difference is it’s slightly smaller and fits more tightly over the cervix.

The cervical cap keeps sperm from entering the uterus and fallopian tubes. If sperm cannot enter the fallopian tubes to fertilize the egg, pregnancy can’t occur.

The cervical cap must be used with spermicide for maximum effectiveness. It stops the sperm from moving, and is a second line of defense against pregnancy.

You must have a prescription to get a cervical cap. This is because the cervical cap needs to be fitted by your doctor.

To insert the cervical cap:

  1. Wash your hands.
  2. Put spermicide in the dome of the cap and spread a thin layer on the rim of the cap.
  3. Put a small amount of spermicide in the folded area between the rim and the dome.
  4. Separate your labia with one hand.
  5. With the other hand, squeeze the brim of the cervical cap.
  6. Insert the cervical cap into your vagina, dome side down.
  7. Push the cap back toward the rectum and then up toward the cervix.
  8. Use your fingers to make certain the cervix is completely covered.

Before you have sex, make sure the cervical cap is still in place. If you have sex multiple times, you don’t need to remove the cap. But you should insert more spermicide. You should also check to make sure the cap is still in position.

The cervical cap must stay in place for at least six hours following intercourse. Don’t remove the cap before then. Doing so greatly lowers its effectiveness.

Keeping the cervical cap in place will give the spermicide time to kill any sperm before you uncover your cervix. But don’t leave the cap in for more than 48 hours. It can increase your risk of bacterial infection.

To remove the cap:

  1. Wash your hands with soap and water.
  2. Squat down, and insert your fingers into your vagina.
  3. Grip the removal cap, and rotate the cap as you push the dome to release the suction.
  4. Pull the cap out.
  5. Wash the cap with soap and water.
  6. Let the cap air-dry.

The efficacy of the cervical cap depends on two things. The first is whether you use it correctly. The second is whether you’ve ever been pregnant.

According to Planned Parenthood, the failure rate for the cervical cap is 14 percent for women who have never been pregnant. There’s a significant loss in the efficacy of cervical caps in women who have been pregnant. According to Planned Parenthood, the failure rate increases to 29 percent in women who have had a vaginal birth.

You can make the cap more effective by always using it exactly as prescribed. It’s also important to regularly check your cap for small holes and other damage. A damaged cap should be replaced immediately. Discoloration of the cap isn’t a problem.

Although it’s not the most effective form of birth control, the cervical cap is very convenient. The benefits of the cap include:

  • can be inserted in advance without interrupting intimacy
  • can be used multiple times
  • low cost
  • no side effects from hormones

The cervical cap has a few disadvantages that include:

  • not the most effective form of birth control
  • doesn’t protect against sexually transmitted infections (STIs)
  • easy to use incorrectly
  • can slide, or be pushed out of place, during intercourse
  • can be uncomfortable for the woman or her sexual partner
  • can’t be used during menstruation
  • requires the use of spermicide, which may cause irritation to either partner

The cap also requires a woman to insert her fingers into her vagina. A woman also needs to check that the cap is in place before sex.

Most women find the cervical cap safe and easy to use. In rare cases it can cause serious side effects. Talk to your doctor if you have any of the following symptoms:

  • burning during urination
  • pain while the cap is in place
  • blood inside the cap when you remove it
  • genital itching or irritation
  • redness or swelling
  • unusual or foul smelling discharge

In addition, women at high risk for STIs should consider another method of contraception. Most spermicides used with the cap contain nonoxynol-9 (N-9). N-9 can increase your susceptibility to HIV and other STIs. Risk is particularly high when N-9 is used multiple times per day.