Cervical Cancer Prevention
The HPV vaccine and screening
- Cervical cancer is one of the most preventable cancers.
- Almost all cases of cervical cancer are caused by a persistent infection with high-risk human papillomavirus (HPV).
- The HPV vaccine and regular screening are the two main pillars of prevention.
- When a persistent HPV infection does progress to cancer, this usually takes 15 to 20 years.
- A positive HPV test (HPV was found) does not mean cancer.
- Vaccination should be tailored to each person's situation, and screening should continue after vaccination too.
- In England, offering the vaccine at age 12 to 13 was followed by about an 87% lower rate of cervical cancer.
- A healthy lifestyle and taking supplements do not replace the vaccine, screening and medical follow-up.
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Two main ways to prevent cervical cancer
HPV vaccine
The vaccine protects against infection with specific types of HPV, including high-risk types that cause cervical cancer. It works best when given early, before any exposure to the virus.
Screening and regular follow-up
Screening helps find high-risk HPV or cell changes in the cervix. Following up on results and treating precancerous changes in time can stop them from progressing to cancer.
The vaccine and screening work together; one does not replace the other
People who have been vaccinated still need screening, because the vaccine does not cover all high-risk HPV types. And people who are screened regularly may also benefit from the vaccine, if their doctor advises it.
The World Health Organization (WHO) goal for eliminating cervical cancer has three parts:
- Fully vaccinating 90% of girls by age 15
- Screening 70% of women with a high-performance test (a highly accurate screening test) by age 35, and again by age 45
- Treating 90% of women who have precancerous changes or cancer
Does a positive HPV test mean I have cancer?
“Anyone who gets HPV will get cervical cancer.”
Because high-risk HPV types are the main cause of cervical cancer, having the virus is sometimes confused with having cancer.
- HPV is very common, and many people get it at some point in their lives without having any symptoms.
- About 9 in 10 HPV infections are cleared by the body’s own immune system within two years.
- When a high-risk HPV type stays in the body, it can cause precancerous changes, but not all of these changes turn into cancer.
- If cell changes do progress to cancer, this usually takes about 15 to 20 years. In people with a weakened immune system, this time may be shorter, about 5 to 10 years.
A positive HPV test does not mean cancer. It means follow-up is needed, matched to your test result and your medical history.
How is HPV passed on?
HPV is mainly passed on through genital skin-to-skin contact. Because the virus is very common and can stay in the body without symptoms for years, it is usually impossible to tell when it was passed on or from whom, and medically this does not change the follow-up plan. What matters is follow-up and screening, rather than finding someone to blame.
HPV vaccine: how many doses, and the best time to get it
Filled circles show the doses needed; a dotted circle means another dose may be needed.
One or two doses (on a two-dose schedule, the doses are at least 6 months apart)
Best time: before any exposure to the virus
One or two doses
On the schedule set by your doctor
Two doses (6 months apart)
Based on your situation and your doctor’s advice; usually up to age 45
At least two doses, three if possible
Fuller protection is needed
Important note on the number of doses
This table is based on WHO recommendations. Some guidelines use a three-dose schedule when vaccination starts at age 15 or older. The right number of doses for you is set by your doctor, based on the type of vaccine, the age you start and the state of your immune system.
Key points about the HPV vaccine
- The vaccine prevents new infections; it does not treat an existing infection or disease.
- No vaccine covers every high-risk type of HPV, so screening is still needed after vaccination.
- The vaccine is recommended for boys too: it protects them against genital warts and some cancers, and it reduces the spread of the virus.
How effective is the HPV vaccine?
Population studies have shown that vaccination, especially before any exposure to the virus, is linked to a sharp drop in cervical cancer:
- In a study in England, in the group offered the vaccine at age 12 to 13, the rate of cervical cancer was about 87% lower, and grade 3 precancerous changes (CIN 3) about 97% lower, than in an unvaccinated reference group.
- In another study in England, no deaths from cervical cancer were recorded from 2020 to 2024 among women aged 20 to 24 in a group where 88 to 90% had been vaccinated at age 12 to 13.
- In a study in Sweden, vaccination before age 17 was linked to about an 88% lower risk of invasive cervical cancer.
Cervical cancer screening: the second part of prevention
Regular screening is needed even after vaccination, because the vaccine does not cover all high-risk HPV types.
How does screening help?
Finding changes early and following up on results gives a chance to treat precancerous changes before they turn into cancer.
The HPV test finds high-risk types of the virus, and the Pap test (Pap smear; in the UK, a smear test) is used to check for cell changes in the cervix.
What can I do to lower my risk of cervical cancer?
Quitting smoking
Smoking raises the risk of cervical cancer in two ways. It weakens the immune defenses of the cervix, and cancer-causing substances in tobacco smoke, which have also been found in cervical mucus, can damage the DNA of cells. Weaker immune defenses can also make an HPV infection last longer.
In an analysis that combined many studies, the risk of squamous cell cervical cancer was about 46% higher in current smokers than in people who had never smoked.
Safer sex and condoms
Condoms give only partial protection, because they do not cover all the skin areas that can be affected.
In a study of 82 young women who had recently become sexually active, always using condoms was linked to about a 70% lower risk of a new HPV infection. This level of protection is not the same for everyone.
Combined birth control pills (combined oral contraceptives, COC)
Long-term use of combined birth control pills is linked to a higher risk of cervical cancer. In a large review, the risk for current users who had taken the pill for five years or more was about 1.9 times that of people who had never used it. After stopping, the risk gradually fell, and about ten years later it was back to the level of people who had never used the pill.
Important note about birth control pills
“1.9 times” means about a 90% higher risk than in people who have never used these pills. It does not mean that your own chance of getting this cancer is 90%. Combined birth control pills also lower the risk of ovarian and endometrial cancer. It is best to choose or change your birth control method with your doctor, weighing the overall benefits, the risks and your situation.
Remember: the vaccine and screening still come first
Alongside the risk-lowering steps above, HPV vaccination and regular screening, with follow-up of the results, are the foundations of cervical cancer prevention. Quitting smoking and safer sex also help lower the risk, but they do not replace these two measures.
Can taking vitamins prevent cervical cancer?
“Taking vitamin supplements, such as vitamin A, prevents cervical cancer.”
The benefits of a healthy diet are sometimes mistaken for the effect of taking supplements.
Taking vitamin supplements is not a proven way to prevent cervical cancer. A healthy diet is good for your general health, but it does not replace the vaccine and screening.
Who needs closer screening?
For some people, screening should start earlier, be done at shorter intervals, or continue for longer.
Women with HIV
Women with HIV have about 6 times the risk of cervical cancer seen in the general population, and precancerous changes may progress faster. WHO recommends that screening with an HPV test start at age 25 and, if the result is negative (HPV not found), usually be repeated every 3 to 5 years.
People with a weakened immune system
People who have had an organ transplant or a blood-forming (hematopoietic) stem cell transplant, or who have end-stage kidney failure or lupus, need a special screening plan. In conditions such as inflammatory bowel disease, rheumatoid arthritis and multiple sclerosis (MS), taking medicines that suppress the immune system also affects the screening plan. When to start and how often to test should be set according to each person’s condition and treatment.
Previous treatment for high-grade precancerous changes (CIN 2+)
After treatment for CIN 2 or CIN 3, the risk of cervical cancer stays higher than in the general population. For this reason, follow-up should continue for at least 25 years after treatment, even past age 65. How often you are tested depends on how far along you are in follow-up and on your previous results.
Is a "wound" or an infection on the cervix precancerous?
What is called a “wound” on the cervix during an exam is, in most cases, a benign change in the surface tissue (cervical ectropion, once called “cervical erosion”). It is neither cancer nor a precancerous change.
Common vaginal and cervical infections are also not the same as a high-risk HPV infection.
Even so, two points are important:
First, a visual exam does not replace screening, and follow-up with a Pap test or an HPV test is still needed.
Second, vaginal suppositories or antibiotics used to treat an infection do not treat cell changes caused by HPV. Those changes have their own, separate follow-up.
Frequently asked questions about cervical cancer prevention
Can cervical cancer be prevented?
It is one of the most preventable cancers. Almost all cases are caused by HPV infection, and combining the vaccine with regular screening can interrupt the process that leads to cancer.
I tested positive for HPV. Will I definitely get cancer?
No. About 9 in 10 HPV infections go away on their own within two years. Only a long-lasting high-risk infection that is not followed up may lead, over 15 to 20 years, to cell changes and then cancer.
Where does HPV come from? Could I have caught it at a swimming pool or a public toilet?
Genital HPV is mainly passed on through close contact of the skin and mucous membranes during sexual activity; penetration is not needed for it to spread. Swimming pools and public toilets are not known ways of catching genital HPV. Because the virus can stay in the body without symptoms for a long time, it is usually not possible to tell when it was passed on or by whom.
At what age should you get the HPV vaccine?
The best time to get vaccinated is before any exposure to the virus, usually at ages 9 to 14. The vaccine may also help at older ages. Whether to have it depends on your age, your vaccination history and your situation, and the decision should be made by your doctor.
How many doses are needed?
Dose schedules are being reviewed. For ages 9 to 20, one or two doses are usually considered, and for age 21 and over, two doses. People with a weakened immune system need at least two doses, and three if possible.
I'm over 26. Is it too late for the vaccine to help?
At these ages, the vaccine’s benefit across the population is smaller, because many people have already been exposed to some HPV types. But that does not mean it is useless, and the decision is made individually with your doctor.
I've had the vaccine. Do I still need screening?
Yes. The vaccine does not cover all high-risk HPV types, so regular screening is still needed.
Should men get the vaccine too?
Yes. The vaccine protects men against genital warts and some cancers, and it also reduces the spread of the virus.
At what age should I start screening, and how often?
When to start screening and how often depends on your age, the type of test, your previous results and the state of your immune system. You can find a table of screening schedules and special situations on the “Cervical cancer screening” page.
My mother or sister had cervical cancer. Am I at higher risk?
Cervical cancer is not known to be an inherited disease; its main cause is a persistent HPV infection. A family history does not usually change your screening plan.
Can taking vitamins prevent it?
Taking supplements is not a proven way to prevent it. A healthy diet is good for you, but it does not replace the vaccine and screening.
How much does smoking matter?
Smoking weakens the immune defenses of the cervix, and the cancer-causing substances in tobacco smoke can damage the DNA of cells. This weaker immune defense can make HPV last longer. Quitting smoking helps lower the risk.
I have a "wound" or an infection. Is it precancer?
Usually not. A “wound” or an infection does not, on its own, mean a precancerous change. Whether you need a Pap test, an HPV test or further checks depends on your symptoms, the exam and your previous results. Treating an infection also does not replace the screening and follow-up you need. To learn about the checks involved, read the Cervical cancer diagnosis page.
I have HIV. Is my screening schedule different?
Yes. For people with HIV, screening starts earlier and is done at shorter intervals.
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