Abnormal smear test: What does it indicate?

A smear test, also known as a pap test, is a procedure to check for changes in the cells of the cervix that might become cancer. Results can either be normal, unclear, or abnormal.

Mr Rahul Nath, leading expert in gynaecology, explains what an abnormal test result indicates, what a smear test involves, and the steps that follow an abnormal smear test.

What does an abnormal smear test indicate?

An abnormal smear test merely indicates that cells have been picked up that may indicate there's a precancer of the cervix. 

What are the causes of an abnormal smear test?

The usual causes of an abnormal smear is infection with human papilloma virus, or HPV. That's actually what we're testing for in the first instance. If the HPV test is positive, then we actually look at this smear to look for cellular changes in the cells that may indicate there may be a precancer. 

How is an abnormal smear test diagnosed?

When women attend their GP, or well woman, clinic, they attend for a routine smear. When women attend the surgery, the nurse or the doctor examining them will obtain a sample of cells from the cervix. They get sent away to a laboratory and those cells are then analysed to identify if there's any evidence of HPV infection. 

If the smear test contains HPV infection, then the laboratory will further analyse the cells to see if they can identify any abnormal cells or a suggestion of precancer. Depending on that grade of abnormality, that will then determine whether women will need a referral to the colposcopy service.   

What is the next step?

The next step is, having had a smear test performed, to wait for the result to come through from the screening services. If the smear test is completely normal, women are called back for a routine smear three years later, if they're under the age of 50, or five years later if they're over the age of 50, but younger than 64. 

In women who've had an abnormal smear test, the outcome may either be to come back for a repeat smear in 12 months, if only HPV infection has been identified but there aren't any abnormal cells. Or, the smear test letter will say you need to be referred to the colposcopy unit, and that takes place if, in addition to HPV infection, we've picked up abnormal cells or a suggestion of precancer cells. 

Is an abnormal smear test an indication of a more serious problem?

Not necessarily. We know that an abnormal smear is very common. Over 400,000 women every year in England and Wales will have an abnormal smear. It can be an indication of a higher-risk problem such as cancer. But, the smear test isn't designed to pick up cancer. The other thing to remember is, the smear just gives reassurance about the cervix. It's not designed to pick up ovarian problems, or uterine-endometrial problems. It's purely a screening test for abnormalities on the cervix. 

If you're concerned about an abnormal smear test, arrange a consultation with Mr Nath via his Top Doctors profile.