What are the current cervical cancer screening guidelines (Pap test and HPV co‑testing), including recommended age intervals, criteria for stopping screening after hysterectomy or age >65, and special considerations for immunocompromised patients, pregnancy, and HPV‑vaccinated women?

Cervical Cancer Screening Guidelines

When to Start Screening

All women should begin cervical cancer screening at age 21 years, regardless of age of sexual debut or other risk factors. 1, 2, 3

• Women younger than 21 years should never be screened, even if sexually active, because cervical cancer is extraordinarily rare in this age group (only 1-2 cases per 1,000 females aged 15-19 years) and screening causes more harm than benefit through unnecessary procedures that increase preterm birth risk. 2, 4

Age-Specific Screening Strategies

Ages 21-29 Years

Screen with cytology (Pap test) alone every 3 years. 1, 2, 3

• HPV testing should not be used for routine screening in this age group, either as a standalone test or as cotesting with cytology. 1, 2
• Reflex HPV testing is acceptable only for triaging ASC-US results in women aged 25-29 years, but this is not routine screening. 1, 2
• The rationale: Most HPV infections in young women are transient and resolve spontaneously without intervention; HPV testing would lead to overtreatment of lesions that would naturally regress. 1, 5

Ages 30-65 Years

The preferred approach is cotesting (cytology + HPV testing) every 5 years. 1, 2, 3

• Acceptable alternatives include:
  • Cytology alone every 3 years 1, 3
  • Primary HPV testing alone every 5 years 5, 3
• All three strategies are considered equally effective by the USPSTF, though cotesting provides the highest sensitivity. 3, 6
• Both liquid-based cytology and conventional Pap smears are acceptable; liquid-based allows reflex HPV testing from the same specimen. 1, 2

When to Stop Screening

Discontinue screening after age 65 years if all of the following criteria are met: 1, 2, 3

1. Adequate prior screening: Either 3 consecutive negative cytology tests OR 2 consecutive negative cotests within the preceding 10 years 1, 2, 5
2. Most recent test within the past 5 years 1, 2, 5
3. No history of CIN 2, CIN 3, adenocarcinoma in situ, or cervical cancer 2, 5

• An HPV-negative ASC-US result counts as a negative test for the purpose of meeting exit criteria. 1, 2
• Once screening is discontinued, it should never be resumed for any reason, including a new sexual partner. 1, 2

Critical Exception to Age 65 Stopping Rule

Women with a history of CIN 2, CIN 3, adenocarcinoma in situ, or cervical cancer must continue routine screening for 20-25 years after treatment or spontaneous regression, even if this extends screening beyond age 65 years. 1, 2, 5

Post-Hysterectomy Screening

Stop all screening after total hysterectomy with cervix removal if: 1, 2, 3

• The hysterectomy was performed for benign disease, AND
• There is no history of CIN 2 or more severe diagnosis in the past 20-25 years, AND
• No history of cervical cancer

Continue screening if: 1, 2

• Subtotal (supracervical) hysterectomy was performed and the cervix remains—follow standard age-based recommendations 1, 2
• History of high-grade precancerous lesions or cervical cancer 2, 5, 3

Special Populations Requiring Modified Surveillance

The standard screening guidelines do NOT apply to the following high-risk groups, who require more intensive, often annual screening: 1, 2, 5

• Women who are HIV-positive 1, 5
• Immunocompromised women (organ transplant recipients, chronic corticosteroid users, chemotherapy patients) 1, 5
• Women with a history of cervical cancer 1, 2
• Women exposed in utero to diethylstilbestrol (DES) 1, 5

Pregnancy Considerations

Routine cervical screening during pregnancy should follow the same age-based intervals as non-pregnant women, but management of abnormal results is more conservative: 1, 2

• For pregnant women with LSIL, colposcopy is preferred, but deferring until 6 weeks postpartum is acceptable. 1, 5
• Colposcopy and cervical biopsy are not acceptable unless high-grade neoplasia or invasive cancer is suspected. 1
• CIN 1 should never be treated during pregnancy. 1, 5

Impact of HPV Vaccination

Screening recommendations are completely unchanged for women who have received HPV vaccination—they follow the exact same schedule as unvaccinated women. 1, 2, 5

• Current HPV vaccines cover approximately 70% of cervical cancers (primarily types 16 and 18) but do not protect against all high-risk HPV types. 1, 2
• Vaccinated women still require lifelong screening because they remain at risk for non-vaccine HPV types. 5

Management of Abnormal Results in Young Women (Ages 21-24)

A conservative approach is mandatory in this age group to avoid overtreatment of lesions that frequently regress spontaneously: 1, 2, 5

• ASC-US: Repeat cytology is preferred; reflex HPV testing is acceptable only for ASC-US (not for other abnormalities). 1, 2
• LSIL: Repeat cytology at 12 months; do not proceed directly to colposcopy. 1
• HSIL: Perform colposcopy, but immediate treatment is not recommended. 1, 2, 5
• CIN 1: Do not treat unless the lesion persists for ≥2 years. 1, 2, 5
• CIN 2: Observation is recommended rather than treatment. 1, 2, 5
• CIN 3: Treat with a diagnostic excisional procedure; hysterectomy is not the primary treatment. 1, 5

Common Pitfalls to Avoid

Annual screening is not recommended for any age group and provides no additional benefit while increasing harms through unnecessary procedures. 1, 2, 5

HPV testing should never be used as a standalone screening test in women under age 30 because the high prevalence of transient HPV infections in this age group leads to excessive false-positive results and overtreatment. 1, 2, 5

Do not screen women under age 21 years under any circumstances—this is a firm recommendation against screening, not a suggestion to individualize. 1, 2, 4, 3

Do not resume screening after age 65 in women who met adequate prior screening criteria, even if they report a new sexual partner or other perceived risk factors. 1, 2