Cervical Screening Programme
Department of Health
The Government of the Hong Kong Special Administrative Region

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Cervical Cells Sampling

  • Look for any obvious abnormality of the cervix. If there are signs of infection, you may postpone the test until the infection has been treated. Reassure the woman if her cervix looks normal.
  • Choose sampling device according to the appearance of the cervix.
  • A cervical ectropion (often wrongly called cervical erosion) is a normal area of columnar cells on the ectocervix. Its appearance is a well-demarcated, red velvety area on the ectocervix. It is more common in premenopausal women. No treatment is needed. If it is present, a smear including its border should be obtained as this represents the upper margin of the transformation zone.
  • Acceptable smear collection instruments include wooden/plastic Ayre's spatula, plastic cervical broom (Cervex brush) and endocervical brush (Cytobrush). Both the conventional and the liquid-based cytology methods for smear examination are acceptable.
  • The sampling technique for conventional smears and liquid based cytology is the same.
  • Any large mucus plug obscuring the external os should be removed with dry cotton ball or swab before taking smear.
  • The transformation zone must be selectively sampled as most cancers and precancers arise from it.
  • In postmenopausal women or those with retracted transformation zone up into the endocervical canal, endocervical brush should also be used in addition to spatula/Cervex brush. It should not be used in pregnant women because of the risk of rupturing the fetal membranes and introducing infection.


  • Insert the spatula into the cervix through the speculum.
  • Press the tip onto the ectocervix and rotate 360 degree in one direction.
  • If an ectropion is present, sampling of its margin using the flat end of a spatula is needed.

Cervex brush

  • Insert the Cervex brush into the cervix through the speculum.
  • Insert the central bristles of the broom into the endocervical canal deep enough to allow the shorter bristles to fully contact the ectocervix. Push gently and rotate 360 degree in one direction for 5 times.

Endocervical brush

  • Use the spatula first to avoid the bleeding result from cytobrush sampling. Use the cytobrush second, as endocervical cells deteriorate more rapidly than ectocervical cells.
  • Insert the cytobrush into the cervix until only the bottommost fibers are exposed outside the os.
  • Slowly rotate 1/4 to 1/2 turn in one direction, Do NOT over-rotate as this may lead to trapping of cells in the bristles, which may not be transferred to the slide.
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