When a normal pregnancy reaches full term the cervix begins to dilate (open) and efface (shorten) to allow the baby out. Incompetent cervix (or cervical weakness/cervical insufficiency) is the term for when this happens early without labour or contractions in the second trimester. It can lead to the waters breaking and late miscarriage or premature birth.
Causes of an incompetent cervix
The cervix may be naturally weak, or the weakness may have been caused during previous pregnancy, previous obstetric trauma, childbirth or uterine abnormalities.
Researchers have found that some people who have an incompetent cervix also have an infection during pregnancy. However, it is not clear whether the infection came first and caused the cervix to open or whether, because the cervix was already open, the infection then spread to this area.
Am I at risk of having an incompetent cervix?
You are considered to be at higher risk of having an incompetent cervix if you have previously had one or more premature births or miscarriages during the second trimester or third trimester. Previous cervical biopsy, or other surgery involving the cervix is also a risk factor.
Treatment for incompetent cervix - the cervical stitch/cerclage
If your healthcare team are concerned about your cervix, you may be offered an internal scan to look at the neck of the womb more closely during your pregnancy.
If you have had one or more premature babies/late miscarriages or cervical surgery in the past and your cervix is getting shorter in early pregnancy, or if you have had a number of premature deliveries but your cervix has not shortened, you may be offered a cervical stitch (also known as a cerclage or cervical suture).
This is a special stitch that is put around your cervix to keep it closed. It can be a planned/elective stitch, put in before or in early pregnancy or an emergency/rescue stitch, put in when the cervix begins to shorten. After the operation you may have some cramps similar to period pains, and you may have bleeding and spotting for a few days.
The stitch is usually removed at around 37 weeks so you can give birth. If you go into labour before then, it will be taken out immediately.
The cervical stitch is normally inserted at the or bottom of your cervix (vaginal stitch). It is usually put in under regional anaesthetic, such as an epidural, which means you are awake but can't feel anything.
If the vaginal stitch fails or if it can’t be inserted, another option is the abdominal stitch (also known as the transabdominal stitch), which is inserted at the top of the cervix before you become pregnant. If you have the abdominal stitch you will need a caesarean section when it comes to time to give birth. This method has a high success rate.
Does the cervical stitch work?
The research on the effects of the stitch is still uncertain but so far it shows that most women who have had cerclage have carried their babies longer than those who have not had cerclage. In a small number of women however the stitch does not prevent the waters from breaking and causing a miscarriage or preterm birth. Other rare complications include infections or excessive bleeding. Ask your doctor to talk you through the risks.
You can also find out more by downloading the NICE patient information leaflet: Keyhole surgery to stitch the cervix to prevent repeated miscarriage.
Treatment for incompetent cervix - progesterone
Progesterone is a hormone that plays a role in maintaining pregnancy. There is mixed evidence on the use of progesterone supplementation to treat cervical shortening but it may be recommended by your consultant in addition to or instead of a cervical stitch.
Treatment for incompetent cervix – bed rest
Your doctor may recommend bed rest as part of your treatment. This has not been proven in research trials to be very effective but it is sometimes recommended as a safeguard. Bed rest can happen at home or in the hospital. It can be complete bed rest, remaining in a sitting or reclining position for most of the time, or moderate bed rest, in which you have to stay mainly inactive but can get up and move around and even go to work if your job is sedentary.
Women have said to us that they suffer from feelings of guilt and self-hatred when they go through miscarriage or premature birth caused by incompetent cervix. This is very sad as the situation is not your fault, and usually there is nothing that you could have done to make a difference. The word ‘incompetent’ in this context is used as a medical term. It does not describe you or your body.
- NICE (2007) Laparoscopic cerclage for the prevention of recurrent pregnancy loss due to recurrent miscarriage, National Institute of Health and Clinical Excellence
- J David, Steer P et al (2010) High risk pregnancy, management options, Elsevier Saunders
- Cockwell HA, Smith GN (2005) Cervical incompetence and the role of emergency cerclage. J Obstet Gynaecol Can. 2005 Feb;27(2):123-9
- Liddiard A, Bhattacharya S (2011) Elective and emergency cervical cerclage and immediate pregnancy outcomes: a retrospective observational study, JRSM Short Rep. Nov 2011; 2(11): 91.
- Conde-Agudelo A, Romero R, Nicolaides K, Et Al. (2013) Vaginal Progesterone Versus Cervical Cerclage For The Prevention Of Preterm Birth In Women With A Sonographic Short Cervix, Singleton Gestation, And Previous Preterm Birth: A Systematic Review And Indirect Comparison Meta-Analysis. American journal of obstetrics and gynecology. 2013;208(1):42.e1-42.e18. doi:10.1016/j.ajog.2012.10.877.
Conde-Agudelo A, Romero R. (2016) Vaginal progesterone to prevent preterm birth in pregnant women with a sonographic short cervix: clinical and public health implications. Am J Obstet Gynecol. 2016 Feb;214(2):235-42. doi: 10.1016/j.ajog.2015.09.102. Epub 2015 Oct 9
- Sosa CG1, Althabe F, Belizán JM, Bergel E. (2015) Bed rest in singleton pregnancies for preventing preterm birth. Cochrane Database Syst Rev. Mar 30;(3):CD003581. doi: 10.1002/14651858.CD003581.pub3.
ℹLast reviewed on October 5th, 2016. Next review date October 5th, 2019.
By Anonymous (not verified) on 20 Oct 2016 - 19:42
Hello. I've been given the go ahead for my abdominal cerclage but I'm scared of the risks as I have adhesions between my bladder and omentum from my previous c section. I'm at risk of bladder injury. Should I risk my health for more children? I have two already. Could this mean I will be on a urine bag for the rest of my life if things go wrong?
By Midwife @Tommys on 21 Oct 2016 - 09:53
Hi, it is difficult to answer your question fully. I am assuming that you are pregnant at the moment if you have been given a go ahead for an abdominal cerclage? There should be notes regarding the extent of the adhesions, I feel it would be beneficial for you to speak to your consultant regarding your concerns and any possible risks before you can make nay decisions. I can assure you that adhesions are not uncommon and women do have more children and do not have permanent bladder injury, it is unlikely for you to end up with a urine bag however I feel you do need to be reviewed and have a full consultation with your notes.
By Midwife @Tommys on 18 Aug 2016 - 11:24
Hi, I am so sorry to hear what you have been through in your last pregnancy and losing your little boy. It is completely understandable that you are feeling so anxious and terrified in this pregnancy. Cervical length is not measured as a routine, only done if there is deemed to be a risk of you labouring early in pregnancy. If there was any risk this should have been identified by the midwife at your booking and a plan put in place for you. If you would like to talk further about this or would like some more information then please do call a midwife on 0800 074 800 or email firstname.lastname@example.org
By Anonymous (not verified) on 18 Aug 2016 - 06:11
Hello. Is cervical length something they will check at the anomoly scan at 16 or 20 weeks. Is it worth paying for the scan private if not. I have no history of miscarriage. We just had to terminate our last pregnancy at 17 weeks because our boy had a severe heart condition. I am terrified of losing this baby too. Thank you for your help.
By Midwife @Tommys on 15 Aug 2016 - 14:43
Hi, It sounds as if you have had a difficult time with the miscarriages and it takes time to recover. However, if you have pelvic pain I would suggest you see your GP or you could call us on 0800 0147 800.
By Midwife @Tommys on 15 Aug 2016 - 10:54
Hi, So sorry to hear about your two miscarriages. Even though about 1:4 pregnancies ends in miscarriage the reasons are sometimes never known and your miscarriage may or may not be associated with cervical problems. Please feel free to contact us at Tommy's on 0800 0147 800 where we may be able to advise you.
By Anonymous (not verified) on 12 Aug 2016 - 17:58
I had two missriage.my water burst when is not time for delivery at sixteen weeks.pls I need answer.
By Midwife @Tommys on 3 Aug 2016 - 12:44
Hi, thank you for your message. As your pregnancy progresses the growing baby exerts pressure on your organs and this, of course includes your pelvic floor. Women often complain of pressure in the lower back, heaviness in the lower abdomen, vaginal pressure and sometimes rectal. This may be due to the weight gain and position of your baby. However with additional symptoms it may also be a sign of preterm labour.
Please feel free to call us at Tommy's 0800 0147 800 as each pregnancy is different.
By Anonymous (not verified) on 3 Aug 2016 - 11:47
I don't have a history of mid trimester miscarriage but I feel a lot of pressure at the moment and it feels like the baby is trying to escape. That is the only way I can explain this feeling. It's making me very anxious about possible incompetent cervix. It's my second baby and I had no complications with my first. No vaginal pressure until I delivered. I hate this feeling and I'm driving myself insane.
By Anonymous (not verified) on 4 Jul 2016 - 05:37
Evn i lost my prrgnency in 21weeks coz of cervic opened, doctor said its impossible to put stitch coz opened cervix centimeter is more, so thy terminated my baby. It was boy
By Deirdre@Tommy's on 13 May 2016 - 09:59
This one is difficult to answer without knowing the specifics of your case. Would you like to call our midwives on 0800 0147 800? They should be able to help. They are on the line Mon-Fri, 9-5pm.
Hope this helps,
By Anonymous (not verified) on 12 May 2016 - 21:40
I want to know if a cervix can grow strong again after being damaged.