Cervical stitch ( OS Wiring / Nylon wiring / Cervical Cerclage )

  • A cervical stitch is a small operation where a stitch is placed around the cervix (neck of the womb). It is usually done between 12 and 24 weeks of pregnancy although occasionally it may be done at later stages in pregnancy, to prevent preterm delivery (early delivery).
  • A cervical stitch is more commonly put in vaginally (transvaginal) and less commonly by an abdominal route (transabdominal)
A cervical stitch

A cervical stitch

Cervical Cerclage

Cervical Cerclage

  • Babies born early (before 37 completed weeks of pregnancy) have an increased risk of short- and long-term health problems. So cervical stitch helps in the prevention of early labor pains and early delivery.
  • Inj corticosteroids are given to mothers who are at increased risk of having early delivery.

  • There are many possible causes for giving birth early. One possible cause is that your cervix shortens and opens too soon. A cervical stitch may help to prevent this if:
    • You have had a miscarriage after 16 weeks of pregnancy
    • You have had a previous birth before 34 weeks of pregnancy
    • Your waters broke before 35 weeks in a previous pregnancy
    • You have had certain types of treatment to your cervix (for example, cone biopsy for treatment of an abnormal smear)
  • In transvaginal ultrasound scans to measure the length of your cervix, if it is found to be short (less than 25 mm long), you may be offered a cervical stitch.

  • Your doctor should discuss the benefits and risks of your individual situation. Sometimes a cervical stitch is not advised because it may carry risks to you and it would not improve the outcome for your baby. This may be if:
    • You have any signs of infection
    • You are having vaginal bleeding
    • You are having contractions (active labor pains)
    • Your waters have already broken

  • Insertion of a cervical stitch takes place in an operating theatre. You may be given a general anesthetic, thanks to which, you will be asleep.
  • In the operating theatre, your legs will be put in supports and sterile covers will be used to keep the operating area clean. The surgeon will hold the cervix and put a stitch around it (see the illustration). The stitch is then tightened and tied, helping to keep the cervix closed. The operation is called a transvaginal cerclage/os wiring/nylon wiring.
  • You will be offered medication to ease any discomfort after the surgery. You will likely be able to go home the same day although you may be advised to stay in the hospital longer (if required).
The transvaginal cervical stitch procedure (left) and once it is completed (right)

The transvaginal cervical stitch procedure (left) and once it is completed (right)

  • This involves an operation to put a stitch around your cervix, through your abdomen, and is also called a ‘trans abdominal cerclage.’ It is an uncommon procedure but may be recommended if a vaginal cervical stitch has not worked in the past or if it is not possible to insert a vaginal stitch.
  • It is done either before you become pregnant or in early pregnancy.
  • It may be done through a cut on your abdomen. This sort of stitch is not removed and your baby would need to be born by cesarean section.

  • Occasionally, you may be offered a stitch as an emergency procedure after your cervix has already opened up, to help prevent having a late miscarriage or preterm birth. This is called a ‘rescue stitch’ and your doctor will discuss the risks and benefits of this with you. This type of stitch has higher risks and doesn’t always work.

  • The risks of surgery include:
    • Bleeding
    • Infection
    • Injury to the bladder
    • Injury to the cervix
    • Your waters breaking early
    • It sometimes not being possible to put the stitch in, for example if your cervix is already too short or too far open.
  • The stitch may not always work and you might still experience a late miscarriage or preterm birth.
  • A cervical stitch does not increase your chances of a cesarean section.

  • After the operation, you may have some vaginal bleeding or brownish discharge for a day or two.
  • Once you recover from the operation, you can carry on as normal for the rest of your pregnancy. Resting in bed is not always recommended.

  • You should contact your doctor if you experience any of the following:
    • Contractions or cramping abdominal pain
    • Continued or heavy vaginal bleeding
    • Rupture of the membrane before labor – an early breaking of water (PROM)
    • Smelly or green vaginal discharge (signs of infection)

  • Your stitch will be taken out at the hospital. This will normally happen at around 36–37 weeks of pregnancy, unless you go into labor before then.
  • You will normally not need any anesthesia for stitch removal. A speculum is inserted into your vagina and the stitch is cut and removed.
  • It usually takes just a few minutes and you may experience some discomfort.
  • You may notice some blood staining or vaginal spotting afterwards. This should settle within 24 hours but you may have a brown discharge for longer. If you have any concerns, you should tell your doctor.
  • If you go into labor with the cervical stitch still in place, you should contact your doctor. It is important to have the stitch removed to prevent damage to your cervix.
  • If your waters break early but you are not in labor, the stitch will usually be removed because of the increased risk of infection.

  • A cervical stitch may help to keep your cervix closed and may reduce the risk of you giving birth early.
  • You may be offered a cervical stitch if you are at risk of giving birth early.
  • A cervical stitch is usually put in between 12 and 24 weeks of pregnancy and then removed at 36–37 weeks unless you go into labor before this.

  • This information aims to help you make the best decision regarding your care. It is not meant to replace advice from a doctor about your own situation.