Parents want to protect their children from harm, and vaccines are one of our best defenses against disease. Now there is a cervical cancer vaccine, the first ever proven to prevent a type of cancer. This vaccine is expected to save the lives of thousands of women each year.

To be more effective, the cervical cancer vaccine needs to be given before a girl becomes sexually active. As a result, the vaccine is now one of the recommended childhood immunizations for girls. Many expert groups endorse the vaccine, including the American Academy of Pediatrics and the American Cancer Society.

The cervical cancer vaccine is also called the human papillomavirus vaccine. It works against the human papillomavirus (HPV), which causes almost all cervical cancer.

What is HPV?
HPV is a virus that is spread through sexual contact, and it is very common. In fact, some doctors think it's nearly as widespread as the common cold. More than six million people in the U.S. get infected with HPV every year. Almost half of those who get infected are between ages 15 and 25.

Most types of HPV are not harmful, but high-risk types can cause cell changes that may lead to cancer. They most often cause cervical cancer, but they may also cause anal cancer and other genital cancers. Some low-risk HPV types cause genital warts.

How well does the vaccine work?
The vaccine is highly effective against the two HPV types that cause most cervical cancers.One vaccine is currently available in the U.S. and another is undergoing review by the FDA:

• Gardasil is available now. It protects against HPV types 16 and 18, which cause 70 percent of cervical cancer. It also protects against HPV types 6 and 11, which cause 90 percent of genital warts.
• Cervarix is being tested by the FDA for safety and effectiveness. It protects against HPV types 16 and 18 and also some other strains of HPV closely related to types 16 and 18. It does not prevent genital warts.

Since the vaccines are still fairly new, experts are not sure how long the protection will last. It is possible that a booster shot may be needed at some point.

How is the vaccine given?
The vaccine is given in a series of three shots over six months. The shots may be given in the arm or the thigh. The second shot is given two months after the first shot, and the third shot is given four months later.

Who should get the vaccine?
The vaccine is most likely to work if it is given before a girl has had any sexual contact. The CDC recommends the vaccine for:

• All girls 11 to 12 years of age, but it may be given as early as age 9
• Girls and women age 13 through 26 who have not been vaccinated or didn't complete the full series of shots

The vaccine is still being studied in males to find out if vaccinating them would reduce the spread of HPV.

Who should not get the vaccine?
A girl or woman should not get the vaccine if she is acutely ill, allergic to yeast, pregnant or trying to get pregnant.

What are the side effects?
Most side effects are minor. The most common ones are slight pain and swelling at the injection site, headache and a low fever. Serious side effects are rare.

Some girls have fainted, which is common in girls after getting an injection. To prevent falls from fainting, a girl should sit or lie down for 15 minutes after getting the shot.

How much does it cost?
The cost for the three-shot series is about $400. Many insurance companies cover the cost. If your insurance pays for standard childhood immunizations, it will likely pay for the cervical cancer vaccine. Check your coverage to be sure.

The vaccine is covered by the Vaccine for Children (VFC) program. This federal program covers vaccine costs for children and teens who are uninsured and for some who are underinsured.

Is the Pap test still necessary?
Yes. The vaccine doesn't protect against all HPV strains that cause cervical cancer, so Pap tests are still very important to find cell changes that could become cancer. Whether or not she has been immunized, a woman should:

• Have her first Pap test within three years of becoming sexually active or at age 21, whichever comes first.
• Continue to have Pap tests as often as her doctor recommends. How often she will need a Pap test depends on her personal health history and risk factors.