There can be several causes of a short cervix, including an overdistended uterus, weak cervical tissue, infection, abnormal uterine activity or inflammation. A short cervix during pregnancy can increase the risk of premature birth, according to the Mayo Clinic.
The average cervical length at 24 weeks of pregnancy is 1.4 inches long. A short cervix measures less than 1 inch, and a very short cervix measures 0.8 inches or less.
Treatments for a short cervix include bed rest, progesterone supplements, changing to a diet higher in folic acid and fatty acids, indomethacin treatment and cervical cerclage, which is a minor surgery. No single treatment has been sufficiently proven to stop premature labor in women with this condition, according to research in "Reviews in Obstetrics & Gynecology."