Cervical Screening

Updated: Aug 22, 2021
  • Author: Nicole W Karjane, MD; Chief Editor: Michel E Rivlin, MD  more...
  • Print


The widespread utilization of routine cervical cancer screening has greatly enhanced physicians' ability to detect cancerous and precancerous changes of the cervix. In the United States, the incidence of cervical cancer fell approximately 70% from 1950 to 1970, followed by an additional 50% drop from 1970 to 2000. [1, 2] These declines likely resulted from implementation of cervical screening programs and an increase in the availability of screening to populations that previously did not have access to testing.

The most common cervical screening test used worldwide was developed by Dr. George Papanicolaou in 1943 when he described how vaginal cells could be collected and stained as a means of detecting cytologic abnormalities of the uterine cervix. [3] Although the test, known as the Papanicolaou smear (or Pap smear or Pap test), continues to be the mainstay of identification of cervical cancer and precancerous lesions of the cervix, it is still not being used to full advantage. It is estimated that 50% of women diagnosed with invasive cervical cancer have never had a Papanicolaou test, and 10% have not had a Papanicolaou test in the 5 years prior to diagnosis. In addition, human papillomavirus (HPV) testing has been available since 2003 as an adjunct to (or possible replacment for) Pap testing, as it is significantly more sensitive for detecting preinvasive lesion. [4, 5, 6, 7, 8]   Sadly, despite widespread screening and treatment of preinvasive lesions, there are still more than 14,000 new cases of cervical cancer in the United States each year and more than 4000 annual deaths from the disease. [9, 10]


Human Papillomavirus

Worldwide, HPV has been detected in as many as 99.7% of cervical carcinomas. [11] Because HPV is implicated in such a high percentage of cervical cancers, a great deal of research has been devoted to characterizing the virus and its role in cervical cancer. HPV is now known to be a small deoxyribonucleic acid (DNA) virus that infects epithelial cells and causes a variety of skin lesions.

To date, more than 100 different types of HPV have been identified, 40 of which may involve lesions of the anogenital tract. Subtypes of the virus can be broadly divided into those that infect stratified squamous epithelium and those that infect mucosal epithelium.

The mucosotrophic types can be further subdivided into low-risk and high-risk types. Of those that affect genital tissues, the low-risk types have been associated with the formation of genital warts. The commonly identified low-risk types include 6, 11, 40, 42, 43, 44, 54, 61, 72, and 81.

The high-risk types are those associated with the formation of intraepithelial neoplasia and include 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68, 69, and 82. These subtypes are considered oncogenic (cancer causing); they are found in 99% of cervical cancers, with types 16 and 18 being found in 70% of them.

Almost all precancerous and cancer lesions are associated with long-term, persistent HPV infection. [12] Fortunately, 90% of infections with HPV are thought to clear within 2 years due to a cell-mediated immune response.  It is the women who fail to clear the HPV infection who are at risk for cervical dysplasia and subsequent cervical cancer.

All HPV subtypes contain early (E) genes and late (L) genes, which are essential to viral integration and replication. L genes encode viral capsid proteins. E genes are responsible for episomal replication. E proteins made by the viral genome promote the activation of host DNA replication mechanisms that can then be used by the virus during its own replication. This is necessary because the virus enters through a disrupted epithelial barrier and infects replicating basal keratinocytes; it then relies on the differentiation of the keratinocytes to reach the surface and be shed for continued infection. The virus replicates only during terminal differentiation of the superficial keratinocytes, which allows it to be shed into the mucosal lumen. The superficial keratinocytes ultimately are shed with the stratum corneum, so no lytic phase exists in the HPV life cycle, as the apoptotic keratinocytes release the virus during degradation in the mucosal lumen (see the image below).

Human papillomavirus infection of epithelium. Human papillomavirus infection of epithelium.

Viral integration into the host cellular genome is a hallmark of malignant progression. This occurs with E1 and E2 genomes (see the image below). E1 protein has helicase activity for replication, and E2 encodes DNA-binding protein for regulation of transcription. Disruption of E1 and E2 allows for dysregulated downstream genes and the expression of E6 and E7 proteins, which are selectively maintained in virally induced tumors. E6 promotes cell growth by inactivation of the p53-related effects, which control cellular proliferation and apoptosis. E7 forms complexes with pRb and functionally inactivates pRb and related proteins, such as EF2, which leads to transcription growth-related proteins. [13]

Human papillomavirus genome. Human papillomavirus genome.

Epidemiology of HPV

In addition to understanding the intricacies of HPV biology, many researchers have looked at the incidence, prevalence, and clearance of the virus, as well as associated risk factors. In the United States, the overall prevalence of the virus is approximately 25% in screened women aged 14-59 years, with the highest prevalence (44.8%) in women aged 20-24 years. HPV prevalence was noted to be 24.5% in women aged 14-19 years, 27.4% in women aged 25-29 years, 27.5% in women aged 30-39 years, 25.2% in women aged 40-49 years, and 19.6% in women aged 50-59 years. Age, marital status, and the number of lifetime and recent sexual partners have been defined as independent risk factors for HPV detection. [11, 13, 14]

Risk factors

Many factors have been studied for an association with regression, including age, race or ethnicity, clinical site, performance of randomized biopsy, number of years of sexual activity, age of sexual debut, number of lifetime partners, length of hormonal contraception use, incidence of sexually transmitted infections, incidence of bacterial vaginosis, condom use, douching practices, and cigarette use. [15] The only identified factor associated with regression of HPV infection, however, is the presence of low-risk HPV type. These findings have contributed to the currently recommended screening guidelines for cervical cancer.


Papanicolaou Test

As mentioned previously, the advent and widespread implementation of routine cervical cancer screening has greatly enhanced the ability to detect cancerous and precancerous changes of the cervix, leading to a decline in the incidence of and mortality from cervical cancer. The Papanicolaou test has been implemented in countries around the world as a screening strategy, and subsequent reductions in rates of cervical cancer by 50% or more have been seen. [16, 17, 18, 19, 20, 21, 22]

Collection of the Papanicolaou test currently involves sampling the cervix at the transformation zone using a spatula or brush.  The transformation zone is where the ectocervix and endocervix meet and dysplasia is most likely to be identified. Since the introduction of the screening test, techniques for sampling cervical cells and analyzing them for dysplastic changes have advanced.

In the conventional Pap test, the cervical sample is transferred to a slide, and a chemical fixative is subsequently applied. While many institutions still use this technique, numerous others use the newer liquid methodologies, which include ThinPrep and SurePath. In these tests, the cervical sample is suspended in a liquid medium and sent to a lab for further processing. Samples go through density gradient sedimentation (SurePath) or filtration techniques (ThinPrep) and are then plated as thin layers on slides.

Once cell collection is complete, the samples are sent to a cytopathologist, who provides a cytologic analysis. The results can be used to triage abnormalities that may require further diagnostic testing, including colposcopy and biopsy of suspicious lesions.

The Papanicolaou test is meant as a screening examination, not as a diagnostic tool. Ideally, this examination would have high sensitivity and specificity, but with the high intraobserver variability that occurs, the reported sensitivity and specificity greatly varies. Sensitivity ranges from 30-87%, and specificity ranges from 86-100%. [23, 24]

In theory, the liquid-based test should have the advantage over conventional collection because of lower incidence of fixation artifact, lower incidence of drying artifact, and less masking of the cellular components. However, studies comparing the 2 techniques have not yielded consistent evidence that the liquid-based test offers significant improvements in sensitivity or specificity, thus both are considered acceptable. [25, 26, 27, 28]

Bethesda system

Papanicolaou test results are routinely reported according to the Bethesda system. This was introduced in 1988 and revised in 2001 and 2008, with the hope of standardizing pathology reports and improving their usefulness. The most recent update to the system was done in 2014 and is described below.  [29, 30]

The 2014 Bethesda System (Adapted from Nayar/Wilbur 2015)  [30]


Indicate conventional smear (Pap smear) vs. liquid-based preparation vs. other


  • Satisfactory for evaluation (describe presence or absence of endocervical/transformation zone component and any other quality indicators, eg, partially obscuring blood, inflammation, etc.)
  • Unsatisfactory for evaluation . . . (specify reason)
    • Specimen rejected/not processed (specify reason)
    • Specimen processed and examined, but unsatisfactory for evaluation of epithelial abnormality because of (specify reason)


  • Negative for Intraepithelial Lesion or Malignancy
  • Other: See Interpretation/Result (eg, endometrial cells in a woman 45 years of age)
  • Epithelial Cell Abnormality: See Interpretation/Result (specify ‘squamous’ or ‘glandular’ as appropriate)


NEGATIVE FOR INTRAEPITHELIAL LESION OR MALIGNANCY (When there is no cellular evidence of neoplasia, state this in the General Categorization above and/or in the Interpretation/Result section of the report--whether or not there are organisms or other non-neoplastic findings)

  • Non-Neoplastic Findings (optional to report)
    • Non-neoplastic cellular variations
      • Squamous metaplasia
      • Keratotic changes
      • Tubal metaplasia
      • Atrophy
      • Pregnancy-associated changes
    • Reactive cellular changes associated with:  
      • Inflammation (includes typical repair)
      • Lymphocytic (follicular) cervicitis
      • Radiation
      • Intrauterine contraceptive device (IUD)
    • Glandular cells status post hysterectomy
  • Organisms
    • Trichomonas vaginalis
    • Fungal organisms morphologically consistent with Candida spp.
    • Shift in flora suggestive of bacterial vaginosis  
    • Bacteria morphologically consistent with Actinomyces spp.  
    • Cellular changes consistent with herpes simplex virus
    • Cellular changes consistent with cytomegalovirus


  • Endometrial cells (in a woman 45 years of age) (Specify if “negative for squamous intraepithelial lesion”)


    • Atypical squamous cells
      • of undetermined significance (ASC-US)
      • cannot exclude HSIL (ASC-H)
    • Low-grade squamous intraepithelial lesion (LSIL) (encompassing: HPV/mild dysplasia/CIN 1)
    • High-grade squamous intraepithelial lesion (HSIL) (encompassing: moderate and severe dysplasia, CIS; CIN 2 and CIN 3)
      • with features suspicious for invasion (if invasion is suspected)
    • Squamous cell carcinoma
    • Atypical
      • endocervical cells (NOS or specify in comments)
      • endometrial cells (NOS or specify in comments)
      • glandular cells (NOS or specify in comments)
    • Atypical
      • endocervical cells, favor neoplastic
      • glandular cells, favor neoplastic
    • Endocervical adenocarcinoma in situ
    • Adenocarcinoma
      • endocervical
      • endometrial
      • extrauterine
      • not otherwise specified (NOS)



Provide a brief description of the test method(s) and report the result so that it is easily understood by the clinician.


If case examined by an automated device, specify device and result.


Suggestions should be concise and consistent with clinical follow-up guidelines published by professional organizations (references to relevant publications may be included)


HPV Testing

Since high-risk HPV has been implicated in more than 90% of cervical cancers, testing for the virus has been utilized as a screening modality either alone or in concert with Papanicolaou tests. In 2003, the US Food and Drug Administration (FDA) approved Digene Hybrid Capture 2 High-Risk HPV DNA Test, which is meant to identify the presence of 14 high-risk HPV types found in cervical samples. This test was approved for use in conjunction with a Papanicolaou test. It is meant to help to triage cytologic abnormalities that are mildly abnormal and may indicate HPV infection and the need for further and closer follow-up.

In March of 2009, the FDA approved Cervista HPV 16/18, which detects the DNA sequences for HPV types 16 and 18 in cervical cells. Differentiating these HPV types gives health care professionals more information on a patient’s risk of subsequently developing cervical cancer. A positive Cervista 16/18 test result indicates whether HPV type 16 or 18 (or both) is present in the cervical sample.

The FDA also approved the Cervista HPV HR test, which is the second DNA test that detects essentially all of the high-risk HPV types in cervical cell samples. The Cervista HPV HR test uses a method similar to the Cervista HPV 16/18 test to detect the DNA sequences of these HPV types. In women aged 30 years or older or in women with borderline cytology, the Cervista HPV 16/18 test can be used together with cytology and the Cervista HPV HR test to assess risk of cervical disease.

Based on the FDA's approval of the first HPV genotyping assay in March 2009, the American Society for Colposcopy and Cervical Pathology (ASCCP) released the Management Algorithm for Using HPV Genotyping to Manage HPV High-Risk Positive/Cytology Negative Women 30 Years and Older. These specific guidelines are discussed in detail in the section on management of cytologic abnormalities.

Several studies have compared the outcomes of using HPV testing alone versus using HPV testing used with cervical cytology. HPV testing has been shown to increase the sensitivity of cytology screening; however, it has lower specificity and, consequently, a lower positive predictive value when used as a primary screening test. [4, 5, 6, 7] HPV does improve specificity in women older than age 30 years and when it is used as part of triaging Papanicolaou test results of atypical squamous cells of undetermined significance (ASC-US). [7]

There is also emerging evidence that primary HPV screening may be a reasonable alternative to cervical cytology screening in women ages 25 years and older.  A working group consisting of representative experts from the Society of Gynecologic Oncology, the American Society of Cytopathology, the College of American Pathologists, the American Society for Colposcopy and Cervical Pathology, the American Cancer Society, the American College of Obstetricians and Gynecologists, and the American Society for Clinical Pathology published interim clinical guidance for practitioners utilizing primary HPV screening. [8]  These recommendations are discussed in detail in the section on primary HPV screening.

A study by Lee et al found through self-reporting by health care providers that low-risk HPV testing, HPV cotesting in women younger than age 30 years, and HPV reflex testing for high-grade, abnormal Papanicolaou test results may lead to unnecessary follow-up and increased medical costs without added benefits. [31] Eliminating low-risk HPV testing in the United States and educating health care providers and patients on appropriate indications for HPV testing are needed in order to deter health care providers from performing such tests when they are unnecessary.


Timing of Screening Tests

Since the Bethesda classification was outlined in an attempt to standardize screening, research has focused on defining the appropriate follow-up for each of the findings. ASCCP reviewed and published their findings in the 2006 Consensus Guidelines. This publication guided the triaging of cytologic findings and appropriate timing of screening until November of 2009 when the American College of Obstetricians and Gynecologists (ACOG) updated the guidelines.

In 2012, ACOG [32, 33] ; the American Cancer Society, American Society for Colposcopy and Cervical Pathology, and American Society for Clinical Pathology (ACS/ASCCP/ASCP) [34] ; as well as the US Preventive Services Task Force (USPSTF) [35] updated their screening recommendations for cervical cancer in asymptomatic women at average risk.

In 2021, ACOG, ASCCP, and the Society of Gynecologic Oncology (SGO) endorsed updated cervical cancer screening guidelines from the USPSTF. The updated guidelines increase the number of options for asymptomatic women aged 30 years and older at average risk to include screening every 5 years with a primary high-risk human papillomavirus (hrHPV) test. The test should be one that is approved by the FDA for stand-alone screening. [36]

Age to begin screening

ACOG, ACOG/ASCCP/ASCP, and USPSTF recommend routine screening in all women at age 21 years, regardless of the woman's sexual behaviors and risk factors. Routine screening is not recommended for those younger than 21 years. [32, 33, 34, 35, 36]

Ages 21-29 years

Women who fall into this age group should be screened every 3 years with liquid-based or conventional cytology alone. [32, 33, 34, 35, 36] Routine screening with HPV testing (alone or cotest with cytology) is not currently recommended by major societies for this age group.  See section on primary HPV screening for interim guidance in women age 25 and older.

Ages 30-65 years

Women aged 30-65 years and older can be screened using cytology alone and cotesting with cytology/HPV.  Women who have negative test results on both tests should not be rescreened before 3 years, although ACOG and ACS/ASCCP/ASCP indicate cotesting every 5 years in this age group is preferred. [32, 33, 34] These findings are consistent with testing that shows that 4-6 years after the original screening, women with negative HPV and cytology have a very low rate of cervical intraepithelial neoplasia (CIN) of grade 2 or higher.

The USPSTF does not state a preference between the cytology alone and the cotesting screening strategies but indicates cotesting at 5-year intervals is a reasonable option in women of this age group who prefer a longer screening interval. [35]

The updated USPSTF guidelines added another option for screening asymptomatic women aged 30-65 years at average risk: FDA-approved primary hrHPV testing alone every 5 years. [37]

Screening cessation

The recommendations are to stop screening once a woman is 65 years old as long as she has had (1) 3 or more documented consecutive negative cytology tests, (2) 2 documented consecutive negative cotest results in the previous 10 years, and (3) no history of CIN 2 or higher, or cancer (ACS/ASCCP/ASCP: ≤20 years). [38, 32, 33, 34, 35, 36]

Women who have a history of CIN-2 or CIN-3 need continued screening for at least 20 years. [34]

The guidelines recommend discontinuing all cervical cancer screening for women of any age who have had a total hysterectomy and who do not have a history of CIN2 or higher. [32, 33, 34, 35]

Special considerations

In general, the reported number of abnormal cytologic findings on Papanicolaou tests during pregnancy is 5-8%, which is not significantly different from nonpregnant patients. Management of abnormal cervical cytology in pregnancy should follow the 2012 consensus guidelines. [39]

For pregnant women over the age of 24 years with ASC-US or LSIL findings, colposcopy is recommended but can be deferred until after delivery.

For pregnant women with ASC-H, HSILs, and AGCs, colposcopy should be performed for all ages. If the lesions are concerning for CIN-2 or -3, these patients should be biopsied. If no lesions are seen on colposcopy, these women should have repeat cytology at 6 weeks postpartum. Endocervical curettage is contraindicated during pregnancy.

The ACS and USPSTF 2012 guidelines did not address special populations (eg, women with a history of cervical cancer, women who were exposed in utero to diethylstilbestrol (DES), women who are immunocompromised) who may require more intensive or alternative screening. ACOG recommends annual screenings for immunocompromised patients, women with history of CIN2, CIN3, or cancer; and women who were exposed to DES in utero. According to the ACOG recommendations, [40]  HIV-positive women should be screened with cervical cytology at the onset of sexual activity or age 21 years, whichever comes first, and should undergo annual screening until they have at least 3 consecutive normal annual cytology results. HIV-infected women age 30 years and older can undergo cytology alone or cotesting. Once there are 3 consecutive negative annual cytology results or one negative cotest, screening can be extended to 3 years. Screening should continue for at least 20 years after treatment of CIN2 or more.

Three vaccines have been developed in an effort to combat HPV and its related disease.  Routine vaccination is recommended for males and females beginning at age 11-12 years and should be given up to the age of 26 years in those who have not yet been vaccinated. [41]  These vaccines all target HPV types 16 and 18, which account for over 70% of all cervical cancers.  Two of the vaccines are also effective against types 6 and 11, which cause 90% of genital warts, and the 9-valent vaccine (approved in 2014) also covers genotypes 31, 33, 45, 52, and 58.  These vaccines are now widely available in the United States and have demonstrated greater than 90% efficacy in preventing CIN2 or worse disease in HPV-naïve populations. Cervical cancer screening recommendations for women who have been vaccinated by the HPV vaccine, however, are currently the same as those for women who have not been vaccinated. [42, 43, 44, 45, 46]


Cytologic Abnormalities

ASC-US and ASC-H cells

Atypical squamous cells (ASC), including those designated as being ASC-US or in the category "cannot exclude high grade" (ASC-H), are an epithelial abnormality diagnosed when the degree of nuclear atypia is not sufficient for the cells to be defined as a squamous intraepithelial lesion (SIL), either low grade or high grade. ASC-H includes atypia that are suggestive of high-grade changes.

Low-grade squamous intraepithelial lesions

Low-grade squamous intraepithelial lesions (LSILs), as defined by the Bethesda system, are suggestive of mild dysplasia or expected CIN-1 on histology and HPV infections with high-risk types. Studies looking at the natural progression of this finding suggest that approximately 50% of these lesions will regress in 24 months, 20% will progress to HSILs, and about 0.2% will progress to cancer in the same time period. [12, 47]

High-grade squamous intraepithelial lesions

HSILs are lesions consistent with moderate and severe dysplasia, corresponding with CIN-2, CIN-3, and carcinoma in situ on histology. This cytology result indicates a high suspicion for an underlying high-grade lesion.  These lesions have a lower likelihood of regression within 24 months, with only 35% regressing, 23.4% persisting, and 1.4% progressing to invasive cancer. [12, 47] Although HPV positivity does affect the time to regression, 90% or more of these lesions will be positive for high-risk HPV, so there is little use in testing for HPV as part of triaging for follow-up care (see the table below).

Table 1. Characteristics of Cervical Cytologic Atypia [47] (Open Table in a new window)

Cytologic Abnormality

Regression to Normal at 24 Months

% (Confidence Interval; CI)

Progression to HSIL at 24 Months

% (CI)

Progression to Invasive Cervical Cancer at 24 Months

% (CI)


68.19 (57.51-78.86)

7.13 (0.8-13.5)

0.25 (0-2.25)


47.39 (35.92-58.86)

20.81 (6.08-35.55)

0.15 (0-0.71)


35.03 (16.57-53.49)

23.37 (12.82-32.92)

1.44 (0-3.95)

Atypical glandular cells

Atypical glandular cells (AGC) seen on cytologic specimens can be associated with squamous cell and glandular abnormalities, including adenocarcinoma of the cervix or the endometrium. According to the Bethesda classification, these abnormalities can be subdivided into lesions associated with cervical, endocervical, or endometrial atypia.


Some studies have suggested that the use of p16 immunohistochemistry can serve as a surrogate for the differentiation of benign lesions from precancerous ones. A cyclin-dependent kinase-4 inhibitor, p16 is expressed in a limited range of normal tissues and tumors and has been identified as a biomarker for HPV transforming infections. Its use has been initiated because, over time, p16 accumulates in the nucleus and can be detected by immunostaining.

A meta-analysis of 97 studies found that p16 immunostaining can be easily applied to cytologic and histologic samples. Additionally, the proportion of p16-positive smears was noted to rise with the increasing severity of cytologic and histologic abnormality.

However, no standardized methodology exists for what constitutes a p16-positive sample; this is particularly true of cytologic samples; thus, a wide range of positivity is reported among the various studies reviewed. Because of the lack of standardization, no current clinical guidelines exist for the use of p16 in primary cervical cancer screening or in the triage of low-grade Papanicolaou smears. However, with time and more standardization, p16 immunostaining may be incorporated into the triage cervical screening. [48]


Cervical Intraepithelial Neoplasia

Precancerous lesions of the cervix are referred to as cervical intraepithelial neoplasia (CIN). During cytologic examination, suspicion for underlying CIN is associated with the presence of koilocytes, which are atypical cells with a perinuclear cavitation or halo in the cytoplasm. In addition, dysplastic cells display an increase in the nuclear to cytoplasmic ratio. These changes are thought to reflect infection with HPV, and when they are seen, additional diagnostic steps, including colposcopy and tissue biopsy, are needed to assess for the histologic diagnosis of CIN.

On histology, the changes that indicate intraepithelial neoplasia include enlarged nuclei, increased nuclear-cytoplasmic ratio, increased hyperchromasia, increased nuclear polymorphism, and increased anisokaryosis. As the severity of CIN increases, the number and abnormal configurations of mitotic figures also increase. The lesions are defined by the amount of the squamous epithelium that is dysplastic.  Low-grade CIN, or CIN-1, displays dysplastic changes in approximately one third of the thickness of the epithelium. CIN-2 involves one half to two thirds of the thickness, and CIN-3 can show full-thickness involvement.

Lastly, carcinoma in situ is diagnosed when dysplasia is seen throughout the epithelium and resembles cervical cancer but has not invaded into the basement membrane. High-grade lesions, such as CIN-2 and CIN-3, are considered to be true precursors of invasive cancer.


Management of Cytologic Abnormalities

The following section discusses management of abnormal cytology (2012 ASCCP Consensus Guidelines). [34]   Note that the management of women age 21-24 years differs from that of women age 25 years and older due to the natural history of HPV infections, lower incidence of invasive lesions and the higher likelihood of regression in that age group.

Management of women with ASC-US

  • HPV testing is preferred; if negative, repeat cotesting in 3 years; if positive, perform colposcopy
  • Repeat cytology in 1 year is acceptable; if negative, repeat cytology in 3 years; if ASC or greater, perform colposcopy

Women aged 21-24 years with ASC-US

  • Repeat cytology in 12 months
  • If repeat cytology is ASC-H, AGC, or HSIL, perform colposcopy; otherwise, repeat cytology in another 12 months
  • If repeat cytology at 24 months is negative, resume routine screening; otherwise, perform colposcopy
  • Alternative is to perform HPV testing; if positive, repeat cytology in 12 and 24 months as above; if negative, resume routine screening.

Women aged 20 years or younger with ASC-US or LSIL

  • HPV infection and minor abnormal cytology results common in adolescents, but invasive cancer is rare
  • Per 2009 ACOG guidelines, Pap tests only recommended beginning at age 21 years, regardless of sexual history; however, Pap tests are still performed in the 20 years or younger age group in some cases because of lack of knowledge of current guidelines
  • Conservative management preferred for this group because of the high likelihood of spontaneous resolution within 2 years of initial infection; abnormal cervical cytology in adolescents, therefore, should be followed according to the recommendations for women ages 21-24 years, as described above

Pregnant women with ASC-US

  • Managed same as nonpregnant women
  • Endocervical curettage (ECC) is contraindicated in pregnant women and should not be collected if colposcopy is performed
  • Deferring colposcopy until at least 6 weeks postpartum is also acceptable

Management of women with ASC-H

  • Perform colposcopy (regardless of HPV status)

Management of women with LSIL

Women aged 25 years or greater with LSIL

  • Perform colposcopy
  • If HPV cotesting was performed and negative, repeat cotesting in 1 year is preferred

Women aged 21-24 years with LSIL

  • Repeat cytology in 12 and 24 months; follow guidelines for ASC-US

Pregnant women with LSIL

  • Managed same as nonpregnant women
  • ECC is contraindicated in pregnant women and should not be collected if colposcopy is performed
  • Also acceptable to defer colposcopy until at least 6 weeks postpartum

Postmenopausal women with LSIL

  • Acceptable options include reflex HPV testing, repeat Pap at 6 and 12 months, and colposcopy
  • If HPV negative or no CIN on colposcopy, repeat cytology in 12 months; if HPV positive or repeat cytology is ASC or greater, perform colposcopy
  • May return to routine screening if 2 consecutive negative cytology results

Management of women with HSIL

  • Refer to colposcopy regardless of age
  • Immediate loop electrosurgical excision is acceptable, except in patients younger than 25 years or who are pregnant

Pregnant women with HSIL

  • Managed same as nonpregnant women
  • ECC and immediate loop electrosurgical excision are contraindicated in pregnant women and should not be performed

Management of women with AGC

Women with AGC, including ASC-NOS, AGC-favor neoplasia, and AIS

  • Refer to colposcopy with endocervical sampling
  • If age 35 or greater or with other risk factors for endometrial neoplasia, endometrial sampling should also be performed.

Women with atypical endometrial cells

  • Perform endometrial biopsy and endocervical sampling. If no pathology found, proceed with colposcopy.

Management of women with benign endometrial cells found in cervical cytology

  • No additional evaluation is required in asymptomatic premenopausal women
  • In postmenopausal women, perform endometrial biopsy

Management of women age 30 years and older who are Pap negative and HPV positive

Repeat cytology and HPV DNA testing in 12 months

  • If cytology negative, HPV negative, repeat cotesting in 3 years
  • If cytology abnormal with any HPV result, perform colposcopy
  • If cytology negative, HPV positive, perform colposcopy

Another option would be to perform HPV 16 and 18 testing

  • If 16 or 18 positive, perform colposcopy
  • If 16 and 18 negative, repeat cotesting in 12 months
  • If cytology negative, HPV negative, repeat cotesting in 3 years
  • If cytology abnormal with any HPV result, perform colposcopy
  • If cytology negative, HPV positive, perform colposcopy

Primary HPV screening

In 2014, the FDA approved one of the HPV DNA tests (cobasHPV test) for primary screening for cervical cancer in women aged 25 years and older. A panel of experts co-sponsored by the ASCCP and the Society for Gynecologic Oncologists (SGO) published recommendations for using primary HPV testing for cervical cancer screening. [49]  In the proposed algorithm, women aged 25 years and older would undergo cervical HPV testing for screening, as opposed to cytology. Women who test negative for high-risk HPV should be re-screened no sooner than every 3 years. For women who test positive for high-risk HPV, HPV genotyping is performed, and those who test positive for HPV 16/18 are referred for colposcopy. Those who are high-risk HPV positive but 16/18 negative undergo cervical cytology. Those with negative cytology results are rescreened in 1 year, and those with ASC-US cytology or greater are referred for colposcopy.  

The above algorithm appears to be at least as effective as current cytology-based screening guidelines and therefore may be considered as a reasonable alternative.