Cervical length scan

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What is this information about?

This information is about your cervical length pregnancy scan. It explains:

• why you are having this scan
• what we look at in this type of scan
• how your scan is done
• what happens after your scan.

Why I have I been given this information?

You have been given this information because you have been asked to come for a cervical length scan. This information will help make sure that you are prepared for your scan and that we get the best information possible about your cervix. This will help us care for you during your pregnancy, delivery (when your baby is born) and postnatally (after your baby is born).

What is the cervix?

The cervix is at the lower part of your womb (uterus) and connects to the birth canal (vagina). Usually, the cervix is closed during pregnancy and opens (dilates) during birth.

Why am I having a cervical length scan?

You may have been asked to come for a cervical length scan if:

• you went into labour naturally in a previous pregnancy between 24+0 and 33+6 weeks pregnant
• you went into labour and had a late miscarriage between 16+0 and 33+6 weeks pregnant
• your ‘waters broke’ between 16+0 and 33+6 weeks in a previous pregnancy. This is also called a preterm prelabour rupture of membranes (PPROM)
• you have had previous surgery on your cervix. This may have been to remove abnormal cells in your cervix, by having a cone biopsy or large loop excision of the transformation zone (LLETZ) procedure
• you have had a precious caesarean section when you were fully dilated (your cervix was fully open)
• you had a cervical stitch (cerclage) in a previous pregnancy
• you have had treatment for cervical cancer (trachelectomy)
• you have a difference in the size or shape of your womb
• you have a health condition which means you are more likely to go into labour early

you are pregnant with two or more babies. For example, twins or triplets.

What does the scan check for?

The scan is done to check how long your cervix is. The scan will also check whether there is any sign of your womb opening, as this can be a sign of your body getting ready to give birth.

When in my pregnancy will my cervical length scan be?

Usually, your scan will be between 16 and 24 weeks, depending on your specific needs. Your midwife or doctor will talk with you about this with you at your antenatal appointments. You may only need one cervical length scan, or you may need the scan repeated every 2 to 4 weeks.

How will you check the cervix?

We will check your cervix by doing an internal (vaginal) scan.

How will the internal scan be done?

• We will ask you to go for a pee before the scan, to make it more comfortable
• You will have a changing area and will be asked to undress from your waist down
• We will give you a gown, towel or sheet to cover yourself with to maintain your dignity
• The scan is usually done with you lying on your back, with your legs apart
• A hand-held scanning device (probe) will be used for your scan
• The probe will be cleaned and covered (with a latex free probe cover) and have gel (sterile lubricating gel) on it
• The probe will be inserted gently into your vagina
• You will feel some movement as the sonographer does their checks.

Do internal scans hurt me or my baby?

No. Most people do not find these scans painful, although they can feel a bit uncomfortable. An internal scan will not cause a miscarriage or harm to your baby.

What happens after my scan?

• For most people, the sonographer will explain the results of your scan to you.
• We may give you a printed copy of the results (scan report) and a copy will also be uploaded to your Badgernotes (your electronic pregnancy notes).
• If you do not understand the results or if you have any questions or concerns, do ask your sonographer at the time of your scan.

What happens if there are findings at my scan which show my cervix is short?

• Lots of people will be checked in our Antenatal Clinics (ANC), Day Assessment Unit (DAU) or the delivery suite after cervical length scans.
• If we are not sure about anything on your scan we may ask for another sonographer to check, or you scan will be looked at by a doctor.
• You may be booked in for extra scans to look at your cervix later on in your pregnancy.
• If your cervix is short, you will see a doctor who will decide the safest way for you to deliver your baby.

How can I find out more about preparing for my scan?

Who can I contact if I need further information or support after I have read this information?