Cone biopsy and LLETZ treatments for removing abnormal cervix cells

LLETZ and cone biopsy are both treatments to remove abnormal cells in cervical area. LLETZ stands for Large Loop Excision of the Transformation Zone.

If you have abnormal cells in your cervix when your cervical screening (a smear test) is performed, you may need some treatment. 

Some of the treatments for abnormal cervix cells may increase the risk of premature birth in future pregnancies. 

What is a colposcopy?

A cervical screening (smear test) may find abnormal cells in your cervix. These changes may go away on their own, but sometimes there is a risk that they could turn into cervical cancer if not treated.

A colposcopy can confirm whether the cells in your cervix are abnormal and if you need treatment to remove them.

A colposcopy is usually carried out in a hospital clinic. A device called a speculum is inserted into your vagina and gently opened. A microscope with a light is used to look at your cervix and liquids are applied to highlight any abnormal areas.

If it's obvious that you have abnormal cells in your cervix, you may be recommended treatment to remove the cells immediately, or advised to wait for the biopsy results. 

What treatment will I have for removing abnormal cervix cells?

There are several ways abnormal cells can be removed from the cervix. 

LLETZ (Large loop excision of the transformation zone)

This is the most common treatment for removing abnormal cervix cells. 

This involves removing the abnormal cells using a thin wire loop that's heated with an electric current.

This can be carried out at the same time as a colposcopy and is usually done while you're awake. Your healthcare professional will use a local anaesthetic to numb the area during treatment. 

Women who have had LLETZ have a higher chance of:

  • premature birth
  • having a baby with a low birthweight
  • your waters breaking early (premature rupture of membranes).

These risks may depend on the amount of cervical tissue that is removed. 

Cone biopsy

A cone biopsy is done less often than LLETZ. This is a minor operation to cut out a cone-shaped piece of tissue containing the abnormal cells. 

This only tends to be used if a large area of tissue needs to be removed. It cannot be done at the same time as a colposcopy and is usually done under general anaesthetic (when you’re asleep). 

Women who have had a cone biopsy have a higher chance of:

  • premature birth 
  • having a baby with a low birthweight
  • needing a caesarean section.

You may have an increased risk of early birth because the cone biopsy has weakened your cervix. In this case you may need monitoring of your cervix and if it is short, a cervical stitch may be advised to prolong the pregnancy. Find out more about prolonging pregnancy. 

Ask your doctor how much tissue was removed. If less than 10mm (1cm) was removed then it shouldn't cause problems. If more than 10mm was removed, they may recommend closer monitoring of your cervix in pregnancy. 

What does this mean for me?

If you have abnormal cells found in your cervix, your doctor should talk to you about all the treatment options available. They should also make sure that the benefits of having any treatment will outweigh the risks (and be clear with you about what these are).

It’s very important that any abnormal cells are treated before they have an opportunity to develop into something more serious. It’s also important to remember that the risk of it causing problems in your pregnancy is small. 

If you are pregnant, you should let your midwife or doctor know if you have had treatment for abnormal cervical cells at your booking appointment.

NHS. Colposcopy. (Page last reviewed: 30 December 2019 Next review due: 30 December 2022)

NHS. Colposcopy treatments. (Page last reviewed: 30 December 2019 Next review due: 30 December 2022) (Page last reviewed: 10 March 2020 Next review due: 10 March 2023)


Review dates
Reviewed: 14 November 2021
Next review: 14 November 2024