An abnormal Pap smear means that some cells collected from your cervix looked different from what’s expected under a microscope. It does not mean you have cancer. Most abnormal cells found during a Pap test are the result of a cervical or vaginal infection and are not cancerous. What it does mean is that your doctor needs more information to figure out why those cells look unusual and whether any follow-up is needed.
The range of “abnormal” is wide. It can be as minor as slightly irregular cells that clear up on their own, or it can signal precancerous changes that benefit from treatment long before they’d ever become dangerous. Understanding where your result falls on that spectrum is the key to knowing what comes next.
Types of Abnormal Results
Pap results are reported using a standardized system that sorts cell changes into categories based on how abnormal they look and which type of cervical cell is affected. Here are the main ones, roughly in order from least to most concerning:
- ASC-US (atypical squamous cells of undetermined significance): This is the most common abnormal result and the mildest. It means some cells look slightly off, but not enough to classify further. Infections, inflammation, and low estrogen levels can all trigger this finding. Many ASC-US results resolve without any treatment.
- LSIL (low-grade squamous intraepithelial lesion): This indicates mild cell changes, often caused by an HPV infection. LSIL corresponds to early, low-level dysplasia. In many cases, especially in younger patients, the immune system clears the HPV and the cells return to normal.
- ASC-H (atypical squamous cells, cannot exclude HSIL): This means the cells look abnormal and there’s a possibility they could be higher-grade changes. It carries more concern than ASC-US and typically leads to closer evaluation.
- HSIL (high-grade squamous intraepithelial lesion): This indicates moderate to severe precancerous changes. HSIL does not mean cancer is present, but these cells are more likely to progress if left untreated. Treatment is generally recommended.
- AGC (atypical glandular cells): This involves a different type of cervical cell and is less common. Because glandular cell abnormalities can sometimes be harder to evaluate, AGC results usually prompt a more thorough workup.
Why HPV Matters
Human papillomavirus is the driving force behind most abnormal Pap results. There are 12 high-risk HPV types, and two of them, HPV 16 and HPV 18, are responsible for the majority of HPV-related cancers. Having one of these strains doesn’t mean you’ll develop cancer, but it does increase the chance that an HPV infection will persist rather than clear on its own, and persistent infection is what leads to precancerous cell changes over time.
This is why many Pap tests now include HPV co-testing. If your Pap comes back abnormal and your HPV test is negative, the likelihood of a serious problem is much lower. If HPV 16 or 18 is detected alongside abnormal cells, your doctor will likely want to take a closer look sooner rather than later. The HPV vaccine (Gardasil 9) protects against the seven HPV types that cause most HPV-related cancers, which is why vaccination has been such a significant tool in prevention.
Non-Cancerous Causes of Abnormal Results
An abnormal Pap doesn’t always point to HPV or precancerous changes. Several everyday conditions can make cervical cells look irregular under a microscope. Yeast infections, bacterial vaginosis, and other vaginal infections can inflame cervical tissue enough to trigger an abnormal reading. Hormonal shifts from menopause, pregnancy, or birth control can also change how cells appear. Even recent sexual activity or the use of vaginal products before your appointment can sometimes affect results.
This is one reason doctors don’t panic over a single mildly abnormal result. In many cases, repeating the test after the underlying cause resolves is all that’s needed.
What Happens After an Abnormal Result
Your next steps depend on the type of abnormality and whether HPV was detected. For the mildest results, like ASC-US with a negative HPV test, your doctor may simply recommend repeating the Pap in a year. For LSIL, HSIL, ASC-H, or AGC results, the standard next step is a procedure called a colposcopy.
A colposcopy is essentially a magnified look at your cervix. You lie on an exam table with your feet in stirrups, and a speculum is placed just like during a regular Pap. Your doctor then positions a colposcope, a lighted magnifying instrument, outside your body to examine your cervical tissue in detail. The colposcope never enters your vagina.
If your doctor sees areas that look abnormal during the colposcopy, they’ll take a small tissue sample (biopsy) for lab analysis. This is typically done with a tool that removes a tiny circular piece of tissue in one quick motion, or by gently scraping the lining of the cervical canal. Most people describe the biopsy as a brief pinch or cramp.
If no biopsy is taken, you can return to your normal activities right away. If a biopsy is performed, you may have mild spotting for a few days. You’ll need to avoid tampons and penetrative sex while your cervix heals. Your doctor will tell you how long to wait. Call your provider if you experience heavy bleeding, severe pelvic pain, or signs of infection like fever or unusual discharge.
Treatment for Precancerous Changes
If your biopsy confirms moderate or severe precancerous changes, treatment aims to remove the abnormal tissue before it has any chance of progressing. The two most common approaches are:
A LEEP (loop electrosurgical excision procedure) uses a thin, heated wire loop to remove abnormal tissue. It’s typically done in a clinic or office under local anesthesia and is relatively quick. A cone biopsy (also called cold-knife conization) removes a cone-shaped piece of cervical tissue and is usually performed in a hospital under general or regional anesthesia, which makes it more involved and more expensive.
Both procedures are effective. Because LEEP achieves comparable outcomes with fewer complications and is easier on patients who may want to become pregnant in the future, it’s often the preferred option when fertility preservation matters. For certain types of glandular abnormalities or more complex cases, a cone biopsy may be recommended instead.
After treatment for moderate-to-severe precancerous changes, you’ll need closer monitoring for a period. The current recommendation is three negative follow-up tests at roughly 6, 18, and 30 months before you can return to a standard three-year screening interval.
How Often You Should Be Screened
Screening guidelines from the U.S. Preventive Services Task Force are based on age:
- Under 21: No screening is recommended, regardless of sexual activity.
- Ages 21 to 29: A Pap test every three years.
- Ages 30 to 65: A Pap test every three years, an HPV test alone every five years, or a Pap plus HPV co-test every five years.
- Over 65: Screening can stop if you’ve had adequate prior results, defined as three consecutive negative Pap tests or two consecutive negative HPV tests within the previous 10 years, with the most recent test within the last five years.
- After hysterectomy: If your cervix was removed and you have no history of high-grade precancerous changes or cervical cancer, screening is no longer needed.
These intervals apply to people at average risk. If you’ve had an abnormal result, your screening schedule will likely be more frequent until your doctor is confident the issue has resolved. An abnormal Pap changes your personal timeline, not the overall recommendation for the general population.