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Screening

What a Pap smear can and cannot tell you

A Pap smear looks for changes in the cells of the cervix before they become cancer. What it can and cannot tell you, which test suits your age, and what happens after an abnormal result.
In this article
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If you have a test result in hand or a decision ahead of you, it is reviewed in detail during the consultation.

In brief

  • Screening is for people who have no symptoms. It finds cell changes on the cervix before they turn into cancer, a process that usually takes years after a persistent infection with high-risk HPV.
  • From 21 to 29 the preferred test is the Pap smear every 3 years; from 30 to 65 it is the HPV test every 5 years. Your own schedule depends on your history and on where you live.
  • An abnormal result is not a diagnosis of cancer. Most abnormal results are mild changes; the next step is a repeat test or colposcopy.
  • Vaccination against HPV does not replace screening, and screening does not prevent the infection. They work together.

Why screen when nothing feels wrong

Screening is for the time when you have no symptoms at all. The test can find changes in the cells of the cervix long before cancer develops. Those changes usually appear after a persistent infection with the human papillomavirus (HPV), and they progress slowly. It is exactly that slow course that gives screening its opportunity.

Screening is not the same as diagnosis

Screening is for a person without symptoms. Diagnosis begins when a screening result comes back abnormal, or when there are symptoms such as bleeding after intercourse or between periods. If either applies to you, the next step is a diagnostic assessment rather than routine screening; it is planned with your physician, or reviewed in an online consultation.

Pap smear, HPV test or co-test: which is right for you?

The choice depends mostly on your age and your medical history. Each test looks at a different part of the same pathway.

HPV test

Detects high-risk HPV before the cells have changed. From 30 to 65 it is usually repeated every 5 years.

Pap smear (cytology)

Examines cells taken from the surface of the cervix under the microscope. From 21 to 29, the Pap smear alone every 3 years is the preferred approach.

Co-test: Pap and HPV together

Both tests are run on a single sample. Between 30 and 65, a co-test every 5 years is an acceptable option, though not the first choice.

Why the starting age differs from place to place

Guidelines do not all begin screening at the same age: some programs start at 21, others at 25 or 30. The right schedule for you depends on your age, your previous results and your individual circumstances; the table below shows the general path.

How often, at each age

Age / groupPreferred testInterval
Under 21Screening not recommendedNot applicable
21 to 29Pap smear (cytology) aloneEvery 3 years
30 to 65Primary HPV testEvery 5 years
30 to 65, alternativesCo-test (Pap + HPV), or Pap aloneCo-test every 5 years; Pap alone every 3
Over 65Screening stops, provided the previous history is adequate and normalNot applicable
Living with HIV, or immunosuppressedScreening starts earlier and is repeated more oftenThe schedule is set with your HIV care team

Why your own schedule may differ. Starting ages and intervals vary between countries, according to each health system’s program and the person’s circumstances. Treat the table as a general guide, not a prescription.

What the test is like, and does it hurt?

  1. You lie on the examination couch. The physician uses a speculum to hold the walls of the vagina open so that the cervix can be seen.
  2. With a small soft brush or spatula, a sample of cells is taken from the surface of the cervix.
  3. The sample goes to the laboratory. Collecting it usually takes a few minutes, is done in the clinic, and needs no anaesthetic.

What it usually feels like

Most people feel brief pressure or discomfort rather than sharp pain, though everyone’s experience is different. The sampling is short, and if you are anxious or uncomfortable, it helps to say so before it begins.

Light spotting afterwards

A small amount of spotting for a short time after a Pap smear is common and usually of no significance.

Before the test

It is better not to have the test during heavy menstrual bleeding. In the days before, avoid douching, vaginal pessaries or creams, and intercourse, since they can reduce the quality of the sample.

Self-sampling for HPV

You take the sample yourself

Where this option is offered, you collect a vaginal sample with a small swab or brush and send it to the laboratory for HPV testing. No speculum examination is needed at this stage. Before you go ahead, check that your physician or laboratory accepts self-collected samples.

Who it helps

Anyone who finds the internal examination frightening or uncomfortable, and anyone without easy access to a physician. Its purpose is to bring screening to people who would otherwise not be screened at all.

Points to keep in mind

  • A self-collected sample is vaginal, not from the cervix itself.
  • If the HPV test is positive, the next step still means seeing a physician for a speculum examination. Self-sampling does not remove the examination; it makes the first step easier.
  • The repeat interval is usually shorter: every 3 years, compared with 5 years for a sample taken by a clinician.

Who needs screening

If I have never been sexually active?

Screening is based on age and any history of sexual contact, not on marriage. HPV can pass through genital skin-to-skin contact and is not limited to intercourse. If you have never had any sexual contact, the risk is very low but not zero; the right decision is made together with your physician.

I have had the HPV vaccine

Screening is still needed. The vaccine does not cover every high-risk type of HPV, so vaccinated women follow the same age-based schedule.

After the menopause

The menopause itself is not a reason to stop. The decision to stop screening depends on age and on the history of previous results, not on whether periods have ended.

During pregnancy

A Pap smear during pregnancy is safe when it is needed and does not cause miscarriage. Many programs, however, defer routine screening until after delivery (about three months after the end of the pregnancy). If your screening falls due while you are pregnant, raise it with your physician.

Is once enough?

No. Screening is a repeating program. A normal result today does not remove the next test; it only sets the interval until it.

After a hysterectomy

It depends on two things. If the uterus and the cervix were both removed, and the operation was not for cancer or a high-grade precancerous lesion, screening usually does not continue. If the cervix remains, screening continues on the usual schedule. If the surgery was for cancer or a high-grade lesion, follow-up continues.

When screening stops

Reaching a certain age is not enough on its own; two conditions are needed together: an age of about 65, and an adequate, normal screening history in the preceding years. Someone who has not been screened for years is not exempted simply by turning 65. If you have had a high-grade precancerous lesion, follow-up continues for years afterwards.

Your result is back: what next?

If the result is normal

Nothing worrying was seen this time. The only thing to do is have the next screening at the recommended interval. A normal result today does not cancel future screening.

If the result is abnormal

An abnormal result does not mean cancer. Most abnormal results are mild changes, and many resolve on their own. The next step depends on the type of result and your age, and is usually one of two things: a repeat test after an interval, or colposcopy.

HPV positive, Pap normal

The virus was found in the sample, but the cells show no change yet. This combination is common and does not, on its own, mean disease. It has its own follow-up schedule.

The exact meaning of terms such as ASC-US, LSIL and HSIL, and the follow-up that each one calls for, depends on your age and history; if you are holding such a result, it can be reviewed in an online consultation.

The HPV vaccine and screening work together

The HPV vaccine

Prevents the infection itself, before exposure to the virus.

Screening

Catches the change before it becomes cancer, the subject of this article.

The two are not alternatives; they are complementary. The vaccine does not cover every high-risk type of HPV, so screening is still needed after vaccination. Screening, on the other hand, does not prevent infection; it finds the consequences earlier.

The global targets for 2030

The World Health Organization’s elimination strategy sets three goals: 90% of girls fully vaccinated by the age of 15; 70% of women screened with a high-performance test by 35, and again by 45; and 90% of women with a precancerous lesion or cancer treated.

Questions patients ask

Neither is better for everyone. The HPV test finds the virus before cells have changed and is the preferred test from 30 to 65; cytology (the Pap smear) looks at the cells themselves and is the preferred test from 21 to 29. Your age and your previous results decide which one you need.

Screening is based on age and any history of sexual contact, not on marital status. HPV can pass through genital skin-to-skin contact and is not limited to intercourse. If you have never had any sexual contact, the risk is very low but not zero; the right decision for you is made in a conversation with your physician.

No. An abnormal result means the cells need a closer look, not that cancer is present. Most abnormal results are mild changes, and many resolve on their own. Depending on the type of result and your age, the next step is usually either a repeat test after an interval, or colposcopy.

This article is for general education and does not replace a consultation with your physician. Reviewed: September 2026.

پرتره پروفسور مژگان کریمی‌زارچی
Author: Professor Mojgan Karimi-Zarchi
Gynecologic Oncologist

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