Cervical cancer screening in the United States starts at age 21 with a Pap test every three years for most people, shifting to co-testing — Pap plus HPV test — every five years from 30 to 65, per the American Cancer Society's 2020 guideline and the U.S. Preventive Services Task Force's 2018 recommendation. The HPV vaccine does not replace screening; vaccinated people follow the same schedule. Screening after 65 can stop, but only if prior results were adequate and normal.
One Women's Health publishes information, not medical advice. Screening decisions belong with your clinician, and personal history — DES exposure, immunosuppression, prior abnormal results — can change this schedule entirely.
Why does screening start at 21?
Because cervical cancer is rare under 25 and HPV infection is common, and treating young cervical cell changes that would clear on their own causes harm without preventing deaths. The American Cancer Society's 2020 guideline actually moved its preferred start to 25, stating that earlier screening picks up transient infections while offering little mortality benefit; USPSTF's 2018 recommendation still holds at 21. Both bodies agree on the reason: most HPV infections in people in their early 20s clear within two years without treatment.
What is the difference between a Pap test and an HPV test?
A Pap test looks at cervical cells for changes caused by HPV; an HPV test looks for the virus itself. Both use the same sample collection. HPV testing is better at identifying who is at risk before changes develop, which is why the ACS's 2020 guideline made primary HPV testing every five years its preferred strategy from 25 to 65, with co-testing and Pap-only as acceptable alternatives. Pap-only every three years remains acceptable where HPV testing is not available, per the same guideline.
What does the schedule look like by age?
The table consolidates the USPSTF 2018 and ACS 2020 recommendations for people at average risk:
| Age | USPSTF 2018 | ACS 2020 |
|---|---|---|
| Under 21 | No screening | No screening |
| 21-29 | Pap every 3 years | Primary HPV test every 5 years (start 25) |
| 30-65 | HPV every 5, co-test every 5, or Pap every 3 | Primary HPV every 5 preferred |
| Over 65 | Stop if adequate prior screening | Stop if adequate prior screening |
"Adequate prior screening" is defined in both guidelines — roughly, normal results on the recommended schedule over the previous decade, per the USPSTF statement.
What happens after an abnormal result?
An abnormal result is a finding to follow up, not a diagnosis of cancer. Follow-up depends on which test was abnormal and how: options include repeat testing in a year, HPV genotyping to identify higher-risk virus types, and colposcopy — a close examination of the cervix with a magnifying instrument. The CDC's 2024 clinician guidance on HPV management lays out the pathways; most abnormal findings resolve without treatment, which is why surveillance, not immediate treatment, is the first step for most results.
Does the HPV vaccine change any of this?
It changes your risk, not your schedule. Vaccination prevents the HPV types that cause most cervical cancers — the vaccine's efficacy against those types is well documented in CDC 2023 coverage and impact data — but screening guidelines for vaccinated people remain the same as for unvaccinated people, because the vaccine does not protect against every high-risk type and many adults were vaccinated after possible exposure. This is stated explicitly in both the ACS and USPSTF documents.
When should you talk to a clinician outside the schedule?
Between screenings for certain symptoms: bleeding after sex, between periods, or after menopause, or unexplained pelvic pain or discharge. The CDC's cervical cancer information lists these as reasons to be seen promptly. Also raise your history at any visit if you have had a total hysterectomy, are immunosuppressed, or were exposed to DES in utero — each of these changes the standard schedule, and the guidelines cover each separately.
What the guidelines establish is a schedule built to catch slow-moving changes while avoiding overtreatment of young people. What they cannot do is know your history — that part belongs to you and your clinician.
For more context, read How HPV Vaccination Actually Lowers Cervical Cancer Risk.
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