Can Early Pregnancy Cause Abnormal Pap Smear?

Yes, early pregnancy can cause abnormal Pap smear results. Hormonal changes alter cervical cells temporarily, and the most common finding is ASC-US.

Your first prenatal appointment comes with a checklist — blood draw, urine sample, maybe an ultrasound. When your OB says the Pap smear came back abnormal, it’s easy to assume the worst. You might wonder if something is threatening your pregnancy or your health.

Here’s the reassuring truth: early pregnancy can trigger an abnormal Pap smear, often due to hormone-driven changes in cervical cells. These findings are usually harmless and temporary. Having an abnormal Pap is common and simply means more testing is needed to rule out cervical cancer — not that it is present.

What Does an Abnormal Pap Mean in Pregnancy?

A Pap smear, also called a Pap test, screens for cervical cancer by collecting cells from the cervix. In pregnancy, the procedure is safe and is often performed at the first prenatal visit if you are overdue for one.

The most common abnormal result is called ASC-US — Atypical Squamous Cells of Undetermined Significance. This means a few cells look slightly different from normal, but not clearly precancerous. Think of it as a yellow flag, not a red one.

During early pregnancy, estrogen and progesterone levels surge, which can change how cervical cells appear under the microscope. These hormonal shifts may produce an ASC-US result even when no disease is present.

Why the News Feels More Alarming During Pregnancy

Hearing “abnormal” during pregnancy feels different because you are not just thinking about yourself — you are worried about your baby. Knowing what can cause an abnormal result can help ease that worry. Potential causes include:

• Hormonal changes: Pregnancy hormones can alter the appearance of cervical cells, sometimes leading to abnormal findings that are not dangerous.
• Inflammation: Inflammation of the cervix — often from a yeast or bacterial infection — can cause a mildly abnormal Pap test.
• HPV infection: High-risk HPV is the underlying cause of most cervical cancers. Having HPV does not affect the outcome of your pregnancy.
• Cervical dysplasia: Precancerous cell changes can occur in pregnancy, but the condition does not progress faster during these nine months.

The important thing to remember: pregnancy doesn’t accelerate cervical cell changes. So even if an abnormal result reflects an underlying issue, your timeframe for follow-up remains safe.

Understanding the Most Common Abnormal Finding (ASC-US)

ASC-US is the most frequent abnormal Pap result. The National Cancer Institute’s guide explains that it means some cells look slightly different from normal but not clearly concerning — most common abnormal result in pregnancy is often due to benign hormone shifts.

If ASC-US shows up, the typical next step is an HPV test. High-risk HPV causes the majority of cervical cancers. A single abnormal result does not mean cancer is present — it means more information is needed to be sure.

For pregnant women, colposcopy is generally safe if recommended. The practitioner examines the cervix with a magnifying device and may take a small biopsy. Studies confirm that pregnancy does not worsen abnormal cell progression, so surveillance is often the appropriate course.

Most of these causes don’t pose an immediate risk to you or your baby. The key is to follow up with your provider to determine which one is at play.

What Happens After an Abnormal Pap During Pregnancy?

If your Pap comes back abnormal, your OB will recommend next steps based on the result type. The sequence is generally similar for pregnant and non-pregnant women.

1. Repeat Pap or HPV test: For borderline results like ASC-US, your provider may re-test in a few months or check for high-risk HPV.
2. Colposcopy: This magnified exam of the cervix is safe during pregnancy and provides a closer look at suspicious areas.
3. Biopsy: If needed, a small tissue sample can be taken during colposcopy; studies show this does not increase miscarriage risk.
4. Surveillance: Low-grade lesions are typically monitored with repeat testing every few months rather than treated right away.
5. Treatment after delivery: High-grade lesions rarely require intervention during pregnancy and can be addressed in the postpartum period.

In most cases, treatment can wait until after your baby is born. High-grade lesions are monitored closely but rarely require intervention while you are pregnant.

How Common Is an Abnormal Pap in Pregnancy?

Abnormal Pap results during pregnancy are less common than many women assume. Per the rare abnormal Pap pregnancy overview from Healthline, such results are uncommon, though pregnancy does not protect against cervical cancer.

Pregnancy-specific rates are comparable, with many abnormal results reflecting benign hormone-related changes rather than true disease.

If you do get an abnormal result, rest assured that HPV and cervical cell changes do not harm your baby. The pregnancy can continue normally, with follow-up testing scheduled after delivery.

Knowing these basics can help you approach follow-up with less anxiety and more confidence.

The Bottom Line

Early pregnancy can cause an abnormal Pap smear, mostly because hormones shift how cervical cells look. The most common result — ASC-US — is rarely a reason to panic. Follow-up with colposcopy is safe during pregnancy, and most abnormalities can be monitored until after delivery.

If your own Pap result shows any cell changes, your obstetrician can review your history and organize surveillance that fits your specific trimester and overall health picture.