Cervical Insufficiency

(Cervical Incompetence)

Reviewed/Revised May 2023
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What is the cervix?

The cervix is the lower part of your uterus (womb). It has an opening that normally stays closed while you're pregnant. When your baby is ready to be born, your cervix will open (dilate) to let your baby out.

What is cervical insufficiency?

Cervical insufficiency is having a weak cervix that opens too early in pregnancy.

  • If your cervix is weak, you could deliver your baby too early for your baby to survive

  • To prevent this, doctors may sew your cervix closed or give you a hormone to insert into your vagina (birth canal)

  • You can't find out if you have a weak cervix until you're pregnant

What causes a weak cervix?

No one knows what causes a weak cervix, but these things can make a weak cervix more likely:

  • Having your cervix injured during a surgical procedure

  • Getting a deep tear in your cervix when you delivered a baby

  • Being born with a birth defect in your reproductive organs

  • Having a short cervix

  • Having had 3 or more miscarriages later in pregnancy

If you had a baby born early because your cervix was weak, there's a good chance that you'll be able to carry another baby the full 9 months. However, the more times you deliver a baby too early because of a weak cervix, the more likely it'll happen again.

What are the symptoms of a weak cervix?

A weak cervix doesn't cause any symptoms other than having your baby too early. Symptoms of the baby coming too early include:

  • Pressure in your vagina (birth canal)

  • Bleeding or spotting

  • Pain in your belly area or lower back

  • Discharge (liquid) coming from your vagina

How can my doctor tell if I have a weak cervix?

Your doctor may think you have a weak cervix if:

  • You've been pregnant before and miscarried in your 2nd trimester

  • During a regular ultrasound (moving pictures of the insides of your uterus), the doctor sees that your cervix is short

  • A regular pregnancy exam shows your cervix has started to open early

How do doctors treat a weak cervix?

If doctors think you have a weak cervix, they may sew your cervix closed (called cervical cerclage) to help keep your baby from being born too early. Usually they’ll remove the stitches before you deliver your baby. If your doctor is planning to deliver your baby by cesarean section (C-section), the stitches may be left in place.

After 22 to 23 weeks of pregnancy, if doctors think you are starting to have signs of labor, they may prescribe medicines called corticosteroids to help the baby's lungs mature. They may also recommend modified bed rest. Modified bed rest means that you should stay off of your feet most of the day.

Cervical Cerclage
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When tissues of the cervix are weak in pregnant women, doctors may place stitches around or through the cervix to keep it from opening until it is time to deliver the baby.
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