A Pap smear — a screening test performed every three years by an OB/GYN during an annual wellness exam — is the best way to check for abnormal cells in the cervix and monitor your risk of cervical cancer. According to the National Cancer Institute, patients who receive regular Pap testing reduce their risk of cervical cancer by up to 80%.
So you might be thinking: okay, then why else might I get an “abnormal” result? Well, the fact of the matter is, according to the National Institute of Health, 3 to 5% of Pap smears come back abnormal. And while there are many potential reasons for abnormal Pap test results — yes, aside from detecting precancerous cells — it first and foremost indicates that further testing is needed.
So, what can cause an abnormal Pap smear result?
We spoke with Dr. Hrishikesh Pai, MD, FRCOG (UK-HON), MSc (USA), FCPS, FICOG, who is the director and founder of the Bloom Group in Mumbai and has more than 35 years of international experience in obstetrics, gynecology, and infertility. With his help, we explain some of the reasons you might receive an abnormal result on your next Pap smear.
1. HPV
Across the board, Human Papillomavirus, or HPV, is the leading cause of abnormal results on a Pap smear.
“As a gynecologist, one of the most common causes I see for an abnormal Pap smear is an infection with the Human Papillomavirus (HPV). This virus is incredibly common, and most sexually active individuals will come into contact with HPV at some point in their lives. In many cases, the body's immune system clears the virus naturally, but certain high-risk strains can lead to changes in cervical cells, which may be detected as abnormalities on a Pap test,” explains Dr. Pai.
2. Trichomoniasis or other STIs
Aside from HPV, other STIs, such as trichomoniasis (more commonly known as herpes), can trigger an abnormal Pap smear result. Herpes can present with various symptoms, such as vaginal itching or burning, pain during urination, and abnormal vaginal discharge, so be sure to have a conversation with your healthcare provider if you think you might be carrying the virus.
3. Vaginal infection
Common vaginal infections, such as yeast infections, can be responsible for abnormal Pap test results. Symptoms of a yeast infection may include vaginal itching or soreness, pain during sexual intercourse, pain or discomfort while urinating, and thick, white vaginal discharge. Yeast infections can also be brought on by the use of antibiotics, so if any of this describes you, a call to your doctor is warranted.
4. Inflammation
According to Dr. Pai, “Another cause for abnormal [Pap smear] results can be inflammation or irritation of the cervix. This can result from a wide range of factors, including sexual intercourse or the use of vaginal douches and certain contraceptives. While these irritants might not lead to long-term issues, they can cause changes in cervical cells that prompt an abnormal Pap smear."
5. Cervical dysplasia
When cervical cells present as "abnormal" but turn out not to be malignant (or cancerous), this is called cervical dysplasia. These cells, if left untreated, however, can eventually become cancerous.
Cervical dysplasia can range from mild to severe and typically requires a biopsy to help your doctor determine the best next steps for you. If the dysplasia is mild, it may not require treatment but should continue to be monitored. In more severe cases, a LEEP procedure may be recommended to remove the affected cells.
6. Cervical cancer
We've said it before and we'll say it again: Pap smears offer the best defense against preventing and detecting cervical cancer. There are two potential types of cervical malignancies, and your treatment plan will depend on which type you have.
The most common type of cervical cancer is called Squamous Cell Carcinoma, which begins in the squamous cells in the outer part of the cervix. The second is Adenocarcinoma, a tumor that begins in the glandular cells that line the cervical canal. Both of these types of cervical cancer, while aggressive, are not typically considered life-threatening and are usually treatable.
7. Your period
Sometimes, it’s something you wouldn’t even consider that may result in an abnormal Pap test. For example, tampon usage or even simply being on your period can potentially affect Pap smear results, so it's often best to wait until after menstruation to schedule your exam.
8. Hormonal fluctuations
“Women need to be aware that hormonal fluctuations can impact Pap smear results. For instance, changes due to menstrual cycles or pregnancy could cause cells to appear abnormal. In these cases, it may be necessary to repeat the test at a different time to ensure accurate results,” explains Dr. Pai.
9. Menopause
Speaking of hormones, as a woman goes through menopause, her estrogen levels gradually decrease to very low levels, which can affect the vaginal tissues. Thinning vaginal tissue can make cervical cells appear abnormal on a Pap smear, which is why it's so important to stay up-to-date on your testing during and after menopause.
10. Lab error
Probably the most frustrating (and unnecessary) reason for an abnormal Pap smear result is a lab error. Yes, labs and technicians can make mistakes, and sometimes those mistakes will affect you and your test results. This is why it's critical to follow up on any abnormal test results with further testing. The peace of mind will be worth it!
11. Autoimmune conditions
Did you know that autoimmune condition(s) can be the culprit behind an abnormal Pap test result? According to the National Institute of Health, there is an association between autoimmune disorders and the occurrence of premalignant or malignant lesions in the cervix. While more research needs to be conducted, early findings do indicate that there is, in fact, a connection.
12. Medications or treatments
“Some medical treatments and medications, such as radiation therapy and corticosteroids, affect your immune system and can result in abnormal Pap smears,” explains Dr. Pai, so be sure to disclose your medical history to your OB/GYN before getting your scheduled Pap test.
13. Smoking or tobacco use
As if you needed another reason to quit smoking, “Substance abuse is also responsible for changing cells and can be at blame for abnormal results,” furthers Dr. Pai. Smokers and tobacco users have an increased risk of developing precancerous lesions of the cervix — also known as dysplasia — as well as an increased chance of developing cervical cancer.
14. Diabetes
Believe it or not, several studies have shown that women with diabetes are at a higher risk of cervical cancer, but knowing your risks and keeping on top of regular screenings can help with early detection and even prevention.
15. Noncancerous cysts or growths
You've probably heard of ovarian cysts, but some other noncancerous cysts or growths can affect cervical cells, resulting in abnormal Pap test results. If this is the case, have a conversation with your doctor about the next best course of action for you.
What to do if you get an abnormal Pap smear result
“My advice to patients is always to follow up with the recommended additional testing or treatment. An abnormal [Pap smear] result is not a definitive diagnosis, but rather a cautionary signal that warrants further investigation. Moreover, I encourage women to discuss any concerns with their healthcare provider, who can provide personalized guidance based on their medical history and test outcomes,” recommends Dr. Pai.
The bottom line? While it can certainly be nerve-wracking, it's important to follow up on any abnormal Pap test results sooner rather than later. And remember, sometimes it’s just a false alarm or a lab error!
Brighid Flynn is a freelance writer based in Philadelphia where she lives with her husband and puppy. She is just beginning her journey toward motherhood.