Shortening of the cervix

Causes of shortening of the cervix

A shortened cervix is a cause for concern for many expectant mothers. This is because it is one of the causes of premature births and therefore involves the risk of complications associated with premature births. A short cervix is diagnosed if it is shorter than 25 mm before the 24th week of pregnancy.

The risk factors for a shortening of the cervix during pregnancy include:

• History of cervical conisation
• Cervical treatments
• Multiple pregnancy
• Cervical hernia during a previous birth
• Malformations of the cervix or uterus

Symptoms of a shortening of the cervix

Cervical shortening can be asymptomatic. Occasionally, the expectant mother feels pain in the lower abdomen, in the lumbar spine or pressure in the perineal area. A shortened cervix can usually be detected by ultrasound. The doctor usually assesses its length using a vaginal probe. This is usually relevant until around the 25th and 26th week. After that, routine measurement of the cervix by ultrasound is no longer recommended, as the cervix gradually shortens physiologically in every woman in the third trimester up to the birth.

Treatment of a shortening of the cervix

The treatment of a shortened cervix consists mainly of the use of progesterone and the insertion of a cervical suture to prevent further shortening and dilation. Bed rest is not currently recommended, as it is of no benefit to pregnant women with a shortened cervix and further increases the risk of thromboembolism. If the cervix shortens below 25 mm before the 24th week, every expectant mother should use progesterone vaginally. If the gynaecologist detects a shortening of the cervix and there has already been a premature birth or a miscarriage, a circular suture is recommended.