Abnormal Pap Smears During Pregnancy

Although abnormal Pap smears are common in pregnancy, actual cancer is not. One out of every 1000 pregnant women will have a cancer. Pregnancy neither increases nor decreases the risk, but when cancer is diagnosed during a pregnancy, it presents a different management challenge. Now two lives are at stake.

The Importance of Pap Smears

In spite of its rarity, the most common cancer for a pregnant woman to get is cervical cancer, or cancer of the mouth of the womb. The fact that cervical cancer is the most frequent malignancy found during pregnancy underscores the importance of a Pap smear as a routine part of prenatal care. It is not only recommended during a pregnancy, but is considered mandatory.

If You Don't Pass the Pap

This is one test you really do want to pass. But if the Pap smear does come back abnormal, don't panic. Often, inflammation or hormonal changes may yield an abnormal but innocent Pap. The Pap smear is not a legitimate diagnostic test, but just a screen. When it's abnormal, the obstetrician must make a real diagnosis by biopsy.

The good news is that, short of actual cancer, all of the pre-cancerous lesions of the cervix--called "dysplasia"--are easily followed with a conservative approach during the pregnancy.

That's because dysplasias of the cervix are notoriously slow growing, allowing a lot of time for a patient to do other things--such as deliver her baby! Thereafter, follow-up with colposcopy (a microscopic exam) can determine if the lesion is worse or even still there. Many dysplasias simply fade away after a pregnancy.

So how dangerous to baby and woman is cervical dysplasia? The first thing one must do is arrive at a "real" diagnosis.

What Happens Next?

If there is a lesion, the obstetrician can trace it. Does it go up into the canal and out of sight, or can it be seen in its entirety? Cervical dysplasia and the progression to cancer is usually by continuous spread--it doesn't jump around to the brain, lung, bone, etc., provided the lesion is surrounded by normal tissue. If a lesion is seen in its entirety under a colposcope (nothing more than a microscope on a stick), one can be pretty sure that there are no hidden surprises. When this is the case, periodic colposcopies are done throughout the pregnancy until management after delivery can be arranged.

What if the entire lesion cannot be seen, and observation through the colposcope demonstrates a lesion that seems to extend up the canal out of sight? This poses a particular problem and a risk, because no diagnosis is complete unless it is based on the complete lesion. If the only part seen is a very mild dysplasia, but nevertheless one that extends up the canal out of sight, it is invasive cancer. Managing it conservatively is a big mistake.