This anatomical formation is nothing more than a muscular ring that is located in the lower part of the uterus and connects it to the vagina. In the center of it there is a channel through which bloody discharge to the outside occurs during menstruation. In addition, through the cervical canal sperm enter the uterus.
Normally, the length of the cervix is 3-4 cm, but during pregnancy this parameter varies by weeks.
How does the size of the cervix change during normal pregnancy for weeks?
Changes in such a reproductive organ as the uterus are observed after 1-3 weeks from the moment of conception. So the first thing a gynecologist can see when looking at the chair is a change in the mucous membrane, which acquires a bluish tinge. This is due to increased uterine blood flow and intensive expansion of the vessels of the uterine neck.
In turn, a change in the hormonal background leads to the fact that the muscle layer begins to increase in volume. As a result, the length of the cervix changes. In this case, the uterus itself becomes softer. The endocervical canal also grows, which is associated with increased production of mucus, necessary to protect the uterine cavity from the entry of pathogenic microorganisms.
The most important indicator, which is taken into account with each pregnancy, is the length of the cervix. It is established during the ultrasound.
As already mentioned above, the length of the cervix is a variable parameter that varies in weeks of pregnancy. So, according to the established norms this should happen as follows:
- 16-20 week - 4-4,5 cm;
- 25-28 week - 3,5-4cm;
- 32-36 week - 3-3.5 cm.
As can be seen, the length decreases as the gestation period increases. This is due to the fact that there is an increase in the size of the uterus itself, in view of the fact that the fetus is growing. In those cases when the cervix is too long for 38-40 weeks of gestation, doctors perform artificial stimulation of the birth process using medicines.
To determine the length of the cervix for weeks of pregnancy, doctors often use a table that indicates the values of this indicator during the entire period of gestation.
What disorders can be associated with the short cervix?
Strongly that the neck (less than 2 cm) can be the cause of various disorders during pregnancy. This phenomenon can be caused by a violation of the hormonal background.
In the presence of a short cervix during pregnancy, it is often diagnosed with "ischemic-cervical insufficiency." This condition is characterized by the inability to retain the fetus in the uterine cavity, which threatens premature birth or miscarriage.
In addition to this hormonal failure, the cause of the development of shortening of the cervix can be scars that have formed after previous pregnancies, scraping or an abortion. It is because of scarring that deformation, shortening and loss of stretch ability occurs.
As a rule, women with this kind of disorders are under the constant control of doctors. In such cases, a woman needs rest and reduced physical exertion on the body. In case of threat of miscarriage or premature birth, a special gynecological ring is put on the cervix, a pessary that keeps it in the necessary position.
Thus, a parameter such as the length of the cervix in the norm during pregnancy varies by weeks. That is why doctors pay special attention to it when they watch a pregnant woman. After all, his change gives a timely warning of the possibility of premature births at a late date or miscarriage - in the early.