Cervical length measurement is necessary for pregnant women to determine the specific condition of the fetus in the uterine cavity. It is very important for pregnant women to measure the cervical length, the normal cervical length is usually 2.5cm~3.0cm. Measuring the cervical length can be a good way to know whether the cervix is shortened, loose, etc., and whether it affects the vaginal delivery, etc., and if the cervix is too short it may lead to the possibility of premature labor. Cervical length is usually measured at around 22-24 weeks of pregnancy and can be detected by ultrasound. If the cervical length is abnormal, measures should be taken. Pregnant women should rest, not do excessive exercise, eat a light diet, and go to the hospital for regular checkups. If there is an abnormal cervical length test result, it is recommended to consult a doctor in time, with the help of the doctor to clarify the cause of the disease, and to carry out targeted treatment or therapy.