Short cervix in pregnancy: normal and pathological

Pregnancy, however easy it may be, requires frequent medical supervision. No healthy woman is immune from unexpected difficulties in the finest period, the timely detection of which helps to safely inform and give birth to a child. The short neck of the uterus during pregnancy is recognized as one of the most common causes of miscarriage or premature birth. Under medical control, the chances of enduring and giving life to a healthy child are significantly increased.

Norm and pathology


The uterus is the most important genital organ, consisting of a neck, an isthmus, the bottom of the uterus and the body, it is in it that a child forms and grows. The neck protects the fetus both mechanically and from the penetration of infections from the vagina. Normally it has the form of a cone with a length of 3 to 5 cm and a dense consistency. Its internal hollow part is called the cervical canal, in which during pregnancy a cork of mucus is formed - it creates protection against pathogens.

It is considered dangerous to shorten the cervix in pregnancy before, cm and less. This length is permissible only at a period of 38 weeks, when the baby is full, and the uterus is preparing for childbirth.

Why is it short?

The short neck of the uterus during pregnancy can be caused by several factors:

  • The uterus from birth has such a structure. Infantile, or a small uterus and the accompanying short neck often prevent the onset of pregnancy or its safe flow.
  • Injury of the cervix during abortions or operations, as well as in difficult births, in which the internal cervical canal is forcibly opened.
  • Strong breaks in past births. Because of the formed scar, the neck loses its elasticity and shortens.
  • "Pregnant" organism prematurely and in large quantities releases the hormone relaxin, which softens, shortens and opens the neck.
  • Pathology of connective tissue, against which premature maturation of the cervix occurs.

Multiple pregnancy, large fetus and polyhydramnios are considered additional risk factors.

Normally, the expansion of the cervical canal and gradual softening of the cervix occurs after 37 weeks. Pregnancy is considered complete, and the baby is ready to be born. From this moment, the external shed opens, the cervical canal first passes the tip of the finger, then one and two fingers. Opens the inner pharynx, smoothes out and gradually disappears, passing into the lower uterine segment. This sign unambiguously indicates an early birth.

The rate of opening the cervix can be different. In maternity females, the neck ripens and shortens much faster than in the first pregnancy. After opening the cervix up to 2 cm, the contraction of the myometrium begins, and labor is started. The cervical canal is stretched so that it can be easily passed through the head first, and then the rest of the fetus. Opening and stretching of the uterine pharynx in labor occurs up to 10 cm.

How to recognize

No special sensations of the short cervix in pregnancy can not cause, and this pathology is revealed only on ultrasound: at 20 weeks or slightly earlier, when the fetus begins to rapidly add weight and significantly pressure on neck. Until that time, the shortening and softening of the cervix is ​​completely painless for the woman.

In rare cases, frightening symptoms may appear, with which you must always consult a doctor. Pulling or cramping sensations in the lower abdomen or vagina, increased uterine tone and strong atypical discharge with or without blood admixture may indicate a shortened neck and signal a threat of miscarriage or childbirth. The reasons for this may be different, but this pathology is sometimes diagnosed.

When the shortened neck is a congenital malformation, it can be determined long before pregnancy by examining the chair and ultrasound diagnosis. A low-lying cervix will also be noticed by the gynecologist at the examination.

Threat to pregnancy

If the neck is shortened to 20-25 mm for a period of less than 37 weeks, under the weight of the fetus, it can open, provoking premature termination of pregnancy and even rapid delivery, threatening multiple cervical tears and of the vagina.

The condition when pregnancy is under threat of interruption due to the inability of the uterus to retain the growing fetus is calledof ischemic-cervical insufficiency. Why there is such a pathology is indicated above.

Another danger for pregnancy with an early shortening of the cervix is ​​the opening of access for infections. The fruit in the stages of active growth is very vulnerable to pathogenic microflora, which can lead, if not to its death, then to malformations. A child can be born with both physical defects and with a violation of the central nervous system. And it is pregnancy that can provoke a spurt of pathogenic flora.


To determine the degree of real danger, it is necessary to pass tests:

  1. Smear from the vagina and urethra for the presence and concentration of pathogenic and opportunistic bacteria (ureaplasma, mycoplasma, thrush, gonorrhea, chlamydia, etc.).
  2. Blood for intrauterine infections (herpes, rubella, etc.) and the level of hormones (progesterone, estrogen, testosterone).
  3. Additional examinations are also prescribed: cardiotocography (for the purpose of diagnosing the tone and possible fights), dopplerography (studying the blood flow and the general condition of the fetus).
  4. The ultrasound of the cervix is ​​being done.

Cervical ultrasound is indicated to all women at a period of 18-21 weeks (during the second screening). Until this time, determining the length of the cervix is ​​inappropriate. Based on the results of the examination, therapy is prescribed and the woman's fate is decided.

The normal values ​​of the length of the cervix are shown in the table:

Gestational age Cervical length
Up to 28 weeks More than 35 mm
28-32 weeks 30-35 mm
32-36 weeks 25-30 mm
After 36 weeks 25 mm and less

Normally, cervical ripening occurs after 37 weeks. Evaluation of the maturity of the cervix can be performed at any time of pregnancy. The data are presented in the table.

Cervical maturity scale according to Bishop:

Criterion 0 points 1 point 2 points
Consistency dense softened around the periphery soft
Length more than 2 cm 1-2 centimeters less than 1 cm
Transmittance of the cervical canal the outer sill is closed or passes the tip of the finger cervical canal is passed for one finger cervical canal for two or more fingers
Position relative to pelvic axis backward backwards or forwards on the pelvic axis

Evaluation of the result:

  • 0-2 points - immature cervix of the uterus;
  • 3-4 points - insufficiently mature (maturing) cervix of the uterus;
  • 5-8 points - mature cervix.

In primiparous women without a previous miscarriage and abortion, the cervix should be closed until 37 weeks. In maternity females, the cervix can be ajar and pass the tip of the finger even in the early stages, and this is the norm option. You do not need to treat this condition.

How to save a child

After finding a short cervix in the early term, doctors perform all the necessary procedures for prolonging pregnancy for the maximum possible time and protecting the fetus. If the situation is uncritical, but only the trend towards a shortening has been noted, the gynecologist is limited to the recommendations:

  • Exercise is unacceptable, involving abdominal tension and abrupt movements. Reasonable activity is only welcomed.
  • Prohibition of lifting weights.
  • Refusal of intimacy.
  • Wearing a bandage.

When the situation becomes close to the critical (neck is shorter than the norm combined with opening in one finger or more), special measures are taken to prevent miscarriage:

  • The woman is instructed to lie most of the time.
  • Intimate relations are excluded both because of the danger of trauma to the weak cervix of the uterus, and because of the possible transmission of pathogenic flora.
  • Drug therapy is carried out to reduce the tone of the uterus using No-shpa, Papaverin, Magnesia, Ginipral, and others.
  • The pessary, or Meyer's ring, is placed on the cervix of the uterus.

The procedure for installing obstetric pessaries is simple enough, takes little time and is performed at a reception in a women's consultation. Its main functions are aimed at preserving and prolonging pregnancy:

  1. prevention of cervical dilatation and all consequences of this condition;
  2. preservation of the cervical plug;
  3. reduced load on the part of the fetus.

Obstetrical ring for all its simplicity is a very effective tool, often helping to inform the child before the due date. Once every 2 weeks the doctor treats the pessary with an antiseptic.

Sometimes, only surgical intervention can save a pregnancy. Operative methods are applied in a hospital:

  • Artificial closure of the cervix by tightening its lateral muscles. A narrow neck will create a time reserve, which is so necessary in the event of the threat of termination of pregnancy.
  • Sewing the uterus at the point of its transition into the cervix. The operation is not simple, it is performed under general anesthesia. It is advisable to perform it in the 1-2-th trimesters. When the uterus of the uterus is sewn, there are great chances for a successful outcome of pregnancy. But problems with the health of the mother or a violation in the development of the fetus can serve as contraindications to the operation.

If the waters are gone, fights begin or the bleeding opens, the sutures will be immediately removed. Further on the situation: an emergency cesarean section is performed, natural births are accepted or (if the term is still small and the clan activity was stopped) a pessary is put.

How to prevent the development of pathology

Far from everything in the state of the body depends on the lifestyle, and pregnancy can provoke the most unexpected processes. Nevertheless, the care of women about their health will help to anticipate and solve problems in a timely manner. The risk of encountering a diagnosis of ischemic-cervical insufficiency will be significantly reduced if the rules are followed:

  • It is recommended to visit a gynecologist on a regular basis, and when planning a pregnancy, this should be the responsibility of every woman. If the short neck is a congenital defect, it can be eliminated before pregnancy.
  • Timely medical examinations will reduce the likelihood of miscarriages, severe childbirth, which in the future could lead to shortening of the cervix.
  • Careful protection will save from abortion.
  • It is necessary to maintain the hormonal background at the proper level. It is influenced by food, activity, rest, and medication.
  • Observing the sexual culture in order to avoid infection.

A pregnant woman should undergo all prescribed examinations, do not ignore suspicious feelings, to protect yourself from stress, stress and illness, it is enough to rest and eat healthy products.

Summing up

A short cervix in pregnancy is not an obstacle to gestation and the birth of a healthy baby. At the twentieth week, when a deviation is detected, it is possible to take various measures and prolong the pregnancy to the point at which the child will already be considered full. The future mother requires compliance with all medical prescriptions and the attitude to a positive result, because excessive excitement is detrimental to pregnancy, and stress to neither mother nor child to nothing.