The test involves a health worker inserting an instrument called a speculum to keep the vagina open. A small spatula is then used to scrape cells from the cervix. These are sent to a laboratory for examination. The NHS Cervical Screening Programme recommends that results should be available within four weeks. If abnormal cells are present, a second smear test may be recommended or a referral to a specialist.
Abnormal cells are irregular in shape.
The smear may also pick up changes to glandular cells lining the cervical canal or endocervix. Changes to these cells may be linked to a rare form of cervical cancer called adenocarcinoma. Some women may be required to have a further test because not enough cells were picked up in the first smear or because there were small cell changes in the cervix. These may, in time, return to normal of their own accord, but will have to be monitored. Laboratories check for three types of dysplasia - mild, moderate and severe dysplasia.