Frequently Asked Questions about HPV Vaccine Safety
- Are human papillomavirus (HPV) vaccines safe?
- How does CDC make sure HPV vaccines are safe?
- How do the benefits of HPV vaccines compare to the risks?
- What HPV vaccines are available in the United States?
- Have serious adverse events been reported after people receive HPV vaccines?
- Can HPV vaccine damage women’s ovaries?
- Has anyone died after receiving HPV vaccines?
- Have FDA and CDC changed any recommendations for the use of HPV vaccines based on vaccine safety monitoring?
- Do HPV vaccines hurt?
- Is HPV vaccine safe for pregnant women?
- Is there anyone who should not get the HPV vaccine?
- What if I have, or my child has, a problem after getting the HPV vaccine?
- Where can I find more information about HPV vaccines?
Yes. All three HPV vaccines – Gardasil 9, Gardasil, and Cervarix – are safe, effective, and recommended by CDC. Many studies have looked at the safety of HPV vaccines in the United States. An overview of these studies can be found on the detailed HPV vaccine safety web page.
Vaccines, like any medicine, can have side effects. Some people who get an HPV vaccine have no side effects at all. Some people report having mild side effects, like a sore arm from the shot for a day or two. The most common side effects are usually mild and go away on their own.
Common Side Effects of HPV Vaccines
- Pain, redness, or swelling in the arm where the shot was given
- Headache or feeling tired
- Muscle or joint pain
Fainting (also known as syncope) and related symptoms (such as jerking movements) can happen after any medical procedure. Some people, especially teens, faint after getting vaccinated. To prevent fainting and related injuries, people receiving HPV vaccines should sit or lie down during vaccination, then remain seated for 15 minutes after the shot.
All vaccines used in the United States are required to go through years of extensive safety testing before they are licensed by the U.S. Food and Drug Administration (FDA). After vaccines are licensed, CDC and FDA continue to monitor each vaccine to make sure it is safe and effective. CDC’s The Journey of Your Child's Vaccine explains how all vaccines are developed, tested, and continually monitored.
Each HPV vaccine was closely studied in clinical trials to make sure it was safe:
- Gardasil 9 was studied in more than 15,000 females and males.
- Gardasil was studied in 29,000 females and males.
- Cervarix was studied in more than 30,000 females.
These clinical trials showed HPV vaccines to be safe and effective. Each vaccine continues to be monitored for any safety problems. This monitoring is especially looking for any rare or new problems that may happen after vaccination.
CDC uses three systems to monitor the safety of vaccines after they are licensed:
- The Vaccine Adverse Event Reporting System (VAERS)
- The Vaccine Safety Datalink (VSD)
- The Clinical Immunization Safety Assessment (CISA) Network.
Read more about these systems on the Vaccine Safety Monitoring at CDC web page.
CDC has carefully studied the risks and benefits of HPV vaccination. HPV vaccination is recommended because the benefits, such as prevention of cancer, far outweigh the risks of possible side effects.
Health decisions are personal, and each person should make choices that are right for themselves and their families. It is important to remember that choosing not to vaccinate is not a risk-free choice—HPV vaccines prevent serious cancers and other diseases in both males and females.
There are three HPV vaccines that are licensed for use in the United States by the FDA and recommended by CDC. These vaccines are Gardasil 9, Gardasil, and Cervarix.
|Who makes it?||Merck & Co., Inc.||Merck & Co., Inc.||GlaxoSmithKline plc|
|What kinds of HPV does it protect against?||HPV types 16, 18, 6, 11, 31, 33, 45, 52, and 58 which cause several types of cancer and genital warts||HPV types 16, 18, 6, and 11, which cause several types of cancer and genital warts||HPV types 16, 18, which cause several types of cancer|
|Who should get the vaccine?*||
|When should the vaccine be given?||
*Recommendations from CDC and the Advisory Committee on Immunization Practices
To find out more about the benefits of HPV vaccination, please visit www.cdc.gov/HPV.
Which adverse events are considered “serious”?
An adverse event is defined by law as serious if it is life threatening or results in death, a persistent or significant disability or incapacity, congenital anomaly or birth defect, hospitalization, or prolongation of existing hospitalization.
While there have been some reports of serious health problems that occurred after HPV vaccination, this doesn’t necessarily mean the problems were caused by the vaccine.
Because Gardasil has accounted for 99% of HPV vaccine doses distributed in the United States, most of CDC’s HPV vaccine safety monitoring and research has focused on this vaccine. From June 2006 to March 2014, approximately 67 million doses of Gardasil were distributed in the United States. VAERS received 29,684 adverse event reports since Gardasil was made available. As with all adverse events after someone receives a vaccine or medicine, these may or may not have been caused by the HPV vaccine.
In the VAERS reports, the most frequently reported symptoms overall were: fainting; dizziness; headache; nausea; fever; and pain, redness, and swelling in the arm where the shot was given. Of the reports to VAERS, 8% were classified as “serious.” For more information, see this 2014 Morbidity and Mortality Weekly Report (MMWR) article: “Human Papillomavirus Vaccination Coverage Among Adolescents, 2007–2013, and Postlicensure Vaccine Safety Monitoring, 2006–2014 — United States.”
CDC and FDA have found no reason to be concerned that Gardasil causes premature ovarian failure (a condition in which a woman’s ovaries stop functioning before age 40). In fact, many different things can cause premature ovarian failure: it can be genetic; caused by chemicals in the environment, cancer treatments, or cigarettes; or caused by an autoimmune disorder or a viral infection. However, in many cases it’s impossible to determine the cause.
From June 2006 to March 2014, when about 67 million doses of Gardasil had been given out in the United States, VAERS received nine reports of premature ovarian failure following receipt of the Gardasil vaccine in the United States. VAERS has received an additional 12 reports of related conditions (“premature menopause,” “ovarian disorder” or “ovarian failure”) after Gardasil vaccination. When adverse events happen after vaccination, it does not necessarily mean they are caused by that vaccination. Because there were no patterns among these reports, and since studies have not found ovarian failure to be associated with HPV vaccination, there is no evidence that the Gardasil vaccine caused the ovarian failure.
Before Gardasil was licensed, its safety was extensively studied in clinical trials. These studies found no difference in amenorrhea (when a woman of reproductive age doesn’t have a period) between women who got Gardasil compared to women who received a placebo (a shot with no medicine in it). Premature ovarian failure was not found to happen in the Gardasil clinical trials.
Some deaths among people who received an HPV vaccine have been reported to VAERS. This does not mean that the vaccine caused the death, only that the death occurred after the person got the vaccine. CDC and FDA review all available information on reports of death following all vaccines, including HPV vaccines.
Between June 2006 and March 2014, when about 67 million doses of HPV vaccine had been given out in the U.S., VAERS received 96 reports of death after people received the Gardasil vaccine. Among the 96 reports of death, many could not be further studied because there was not enough information included in the report to verify that a person had died. In 47 of the reports, CDC verified that the person had died through review of medical records, autopsy reports, and death certificates. After careful review of every known case of death that has happened after Gardasil vaccination, CDC concluded:
- There is no diagnosis that would suggest Gardasil caused the death
- There is no pattern of death occurring with respect to time after vaccination
- There is no consistent vaccine dose number or combination of vaccines given among the reports
Yes. When fainting (or syncope) was found to happen after vaccination, FDA changed Gardasil’s guidance for doctors to include information about preventing falls and injuries from fainting after HPV vaccination. CDC and the Advisory Committee on Immunization Practices included this guidance in the recommendations for HPV vaccination. CDC continues to remind doctors and nurses to observe this guidance and to share this information with all their patients.
Some people who get the HPV vaccine may have some pain in their arm where the shot was given. Usually this pain is mild and goes away within a few days. Swelling and redness also sometimes occur after HPV vaccination. In studies comparing the safety of Gardasil and Gardasil 9, these reactions, called “injection site reactions,” were reported more often after Gardasil 9 vaccination.
Because the vaccines weren’t tested in pregnant women during clinical trials, HPV vaccines are not currently recommended for pregnant women. However, some pregnant women receive HPV vaccines because they don’t know that they are pregnant at the time of vaccination.
CDC and vaccine manufacturers have monitored and studied HPV vaccine safety in women who received the vaccine when they were pregnant. Close monitoring has not found any health concerns. If a woman receives HPV vaccine and later learns that she is pregnant, there is no reason to be alarmed.
Any woman who learns she was pregnant at the time she received an HPV vaccine is encouraged to contact the vaccine manufacturer. This will help us learn how pregnant women respond to the vaccine.
- Pregnant women who received Gardasil 9 or Gardasil can contact Merck at 1-877-888-4231 if they have questions related to getting the vaccine while pregnant.
- Doctors should report Gardasil 9 vaccination during pregnancy as early in the pregnancy as possible using Merck Pregnancy Registries.
- Pregnant women who received Cervarix can contact GlaxoSmithKline at 1-888-452-9622
Some people should not get the HPV vaccine or should wait.
- Anyone who has ever had a life-threatening allergic reaction to any component of HPV vaccine, or to a previous dose of HPV vaccine, should not get the vaccine.
- If you or your child is considering receiving Gardasil 9 or Gardasil, tell your doctor about any severe allergies, including an allergy to yeast.
- If you or your child is considering receiving Cervarix, tell your doctor about any severe allergies, including an allergy to latex.
- HPV vaccine is not recommended for pregnant women. However, receiving HPV vaccine when pregnant is not cause for alarm. Women who are breastfeeding may get the vaccine.
- People who are mildly ill (low-grade fever of less than 101 degrees, a cold, runny nose, or cough) when a dose of HPV vaccine is planned can still be vaccinated. People with a moderate or severe illness should wait until they are better.
If you or your child is having a severe allergic reaction or other health emergency, call 9-1-1 or go to the nearest hospital.
Look for any signs or symptoms that concern you, such as signs of a severe allergic reaction, very high fever, or behavior changes. Signs of a severe allergic reaction can include hives, swelling of the face and throat, difficulty breathing, a fast heartbeat, dizziness, and weakness. These would start a few minutes to a few hours after the shot is given.
After seeing a doctor, the reaction should be reported to the Vaccine Adverse Event Reporting System (VAERS). This system is used to report any side effect or adverse event following vaccination. Your doctor can file this report, or you can do it yourself through the VAERS website or by calling 1-800-822-7967.
For additional information on HPV vaccines and CDC’s recommendations, please visit www.cdc.gov/HPV.