An incompetent cervix, otherwise termed cervical insufficiency, happens when weak tissues of the cervix result in either preterm birth of the newborn – an infant whose organs are yet to develop fully, or miscarriage i.e. loss of the baby while still in the womb before completion of pregnancy.

Also Read: Miscarriage: Signs And Symptoms Not To Ignore
Incompetent Cervix

In the female reproductive system, the cervix is a 1 inch-long robust fibromuscular organ shaped like a cylinder, situated at the lower end of the uterus which opens into the vagina. In normal, healthy women, the cervix becomes more pliable, reducing in length and dilating at the end of the pregnancy phase, to facilitate giving birth easily. However, in instances of an incompetent cervix/cervical insufficiency, owing to abnormal structure, fragile assembly or impaired tissues, the cervix loosens and opens rather early on and in a quiet manner during the pregnancy phase.

Causes Of Incompetent Cervix:

Various factors can prompt an incompetent cervix, such as:

  • Irregular shape/structure of the cervix or uterus
  • Having undergone surgery in the cervix in the past
  • Shorter than normal length of the cervix
  • Damage to the uterus incurred from previous miscarriage or childbirth
  • Genetic ailments hampering the fibrous tissue – collagen, that forms the cervix
  • Being exposed to diethylstilbestrol (DES), a synthetic form of the hormone estrogen, during pregnancy

Also Read: Estrogen: Structure, Crucial Functions, Adverse Effects


Usually, no obvious signs are experienced by the woman in early pregnancy that imply an incompetent cervix or cervical insufficiency. During the period between 14 and 20 weeks in the gestational phase, a slight uneasy feeling along with spotting occurs in some cases.

Furthermore, certain indications that could suggest an incompetent cervix include:

  • Low back pain and pelvic discomfort that arises suddenly
  • Minor instances of abdominal cramps
  • Vaginal discharge with light bleeding as well sometimes


An incompetent cervix can be identified only when the woman is pregnant and in quite a few cases, ascertaining the abnormal structure of the cervix is challenging, especially if it is the first pregnancy.

The doctor enquires about the medical history and past gynaecological complications that the patient may have encountered and if they have had any miscarriage during the second trimester, surgery or other procedures in the cervix, such as cervical dilation, previously. This helps the physician confirm the instance of an incompetent cervix.

Additionally, diagnostic tests of transvaginal ultrasound and pelvic exam are carried out, to measure the length of the cervix to detect any shortening or widening, besides checking if foetal membranes are protruding into the cervix and vagina. These procedures can be conducted during pregnancy, but most other laboratory protocols are not recommended in the gestation period. However, visual analyses like an MRI scan and ultrasound imaging can be done prior to pregnancy, to determine if there are any abnormalities in the uterus, cervix, vagina, which could increase the risk of an incompetent cervix.


Once the healthcare provider detects an incompetent cervix, the major treatment approach is surgery through a procedure termed cervical cerclage. This protocol entails stitching together the cervical tissues with fortified sutures to make the tissues stronger and ensure a healthy pregnancy. The procedure of cervical cerclage is usually performed between 12 to 14 weeks of pregnancy and the stitches are removed around week 37. This tightens, closes and rectifies the structure of the cervix and aids in a normal timely pregnancy for the patient.