Pregnancy

Fetal position: longitudinal, transverse, oblique

Helen George - Midwife
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Medically reviewed: 29, December 2023

Read Time:6 Minute

Position of the fetus: what is right and what to do if baby is not head down?

 

Pregnancy is a dynamic process, the result of which is delivery. The course of pregnancy affects the tactics and course of childbirth. One of the most important characteristics of pregnancy, which determines the possibility of delivery through the natural birth canal, is the position of the fetus in the uterine cavity.

What are the variants of the position of the fetus?

The position of the fetus in the uterus is the ratio of the axis of his body along the length to the long axis of the uterus. The presentation refers to the ratio of the part of the fetus that is directed towards the exit from the uterine cavity. Both the presentation and the position of the fetus in the uterus may be wrong and correct.

The possibility of natural childbirth is determined by the position of the child at the time of their onset. If the fetus is not properly positioned, delivery will not occur naturally.

Classification of possible positions and presentations of the fetus in the uterus is given in the table:

  • Correct position of the fetus
  • Longitudinal position of the fetus
  • Oblique position of the fetus
  • Unstable fetal position
  • Malposition
  • The transverse position of the fetus
  • Wrong fetus position
  • Fetal head presentation
  • Pelvic fetal presentation
  • Gluteal presentation of the fetus
  • Low fetal presentation.

These tables are common, because some of the types of pelvic and irregular fetal presentations are subdivided into several subspecies. This is not so important as the above division, due to a slight influence on the choice of tactics of labor.

Do not forget that the unstable position and presentation of the fetus in the uterus is a variant of the relative norm, since it is limited by the time interval of pregnancy.

How is the position and presentation of the fetus formed?

After conception and entering the uterine cavity, a fetal egg is attached to one of its walls. At this time, the embryo is located at the head end to the exit from the uterus. This persistent position of the fetus is noted until the formation of the placenta and umbilical cord.

After reaching 16-20 weeks of pregnancy, the umbilical cord is lengthened, the child has active movements. So there is a potential opportunity to purchase the unstable position of the fetus. Because the conditions to acquire a different position of the fetus in the uterus, more than enough. Therefore, the unstable position of the fetus is a variant of the absolute norm before the indicated time.

After the onset of 36 weeks of gestation, the size of the fetus increases, and the uterus does not grow. There are very few places for making active turns. Thus, the unstable position of the fetus becomes resistant. The child keeps within a certain position, which is preserved until the very birth. On how it lies, depends on the name of the correct or incorrect position of the fetus and the possibility of normal births.

Very rarely it can change, which must be diagnosed during a routine examination of a pregnant woman.

Longitudinal position of the fetus

Longitudinal position of the fetus If the axis of the body of the embryo coincides with the axis of the uterus, such a relationship is called the longitudinal position of the fetus. This is the only option for the normal location of the child in the case of a headache (head towards the exit from the uterus). With this option, natural births are possible in the absence of other abnormalities. Obstetricians-gynecologists of the old school achieved the longitudinal position of the fetus even before the very birth, turning the child over with the hands through the abdominal wall of the pregnant woman. Today, this manipulation is categorically contraindicated due to high risk.

The transverse position of the fetus

The relationship between the longitudinal axis of the embryo and the longitudinal axis of the uterus, at which a right angle is formed, is called the transverse position of the fetus. This means that the child lies across the pelvis. Naturally, if such a situation persists until the delivery itself, delivery is possible only by cesarean section.

Fortunately, this position of the fetus in the uterus is rare. To determine it may be excessive physical activity or bed rest, anomalies and other abnormalities of the child’s development.

Very often the transverse position of the fetus is mistakenly called the transverse presentation of the fetus. It is not right. Preposition can only be head or pelvic. The use of the term transverse presentation of the fetus implies its analogous position. After all, childbirth with this option is generally impossible. Consequently, there can not be a presenting part, as well as the most transverse presentation of the fetus. The parts of the child facing the exit from the uterus, in this case, can only be back or tummy.

Oblique position of the fetus

Oblique position of the fetus is an intermediate option between the longitudinal and transverse is the oblique position of the fetus. In this case, its longitudinal axis is at an angle to the axis of the uterus.

The baby lies diagonally

This anatomical variant can not be called pathological, since it almost always becomes longitudinal. As soon as the uterus begins to come into tonus, the size of the uterine cavity decreases and the divergence of the axes begins to be eliminated. They become unidirectional, which allows you to translate the oblique wrong position of the fetus in the longitudinal. In such cases, natural childbirth is possible.

The exception is women with a clinically and anatomically narrow pelvis. They have an internal volume of the pelvis so small that the head of the child is unable to insert and the wrong oblique position of the fetus is preserved. There is a risk of a transverse fetal position, which also requires delivery by caesarean section.

Low fetal position

The term “low fetal presentation” is the only indicator of the relationship not of the longitudinal, but of the transverse axes of the fetus and uterus.

This means that the child in the uterine cavity should be located above the entrance to the small pelvis. If there is a lowering of the head with its insertion into the pelvis, this may be evidence of the beginning of normal or premature birth, depending on the timing of pregnancy. A low fetal presentation is normal after 38 weeks.

At the same time, nothing needs to be feared. The baby and the uterus are ready for delivery. In case of threat of premature birth, a low presentation of the fetus occurs earlier than the indicated time. Pregnant should follow all the recommendations of specialists for the further preservation of pregnancy.

Pelvic fetal position

Pelvic presentation of the fetus If the child is facing the pelvic end to the exit from the uterus, this option is considered a pelvic presentation of the fetus.

It can not be called normal. Therefore, it refers to the incorrect position of the fetus. Births with this presentation are possible through natural birthmarks. But due to a large number of complications, modern midwives recommend delivery by caesarean section. Specific tactics are chosen individually, because it depends on a variety of factors: the size of the pelvis of a woman and a child, the nature of labor and many others.

Gluteal position of the fetus

Gluteal presentation of the fetus The most frequent subspecies of the pelvic is the breech presentation of the fetus. This means that the child is born with glutes. They are the first to leave.

In some cases, the legs may appear first. In this case, they speak not about the breech presentation, but about the pelvic floor. The presentation of the fetus with the buttocks to the exit from the pelvis refers to the non-standard and requires either special skills of midwives to take delivery naturally, or conduct a caesarean section. Tactics are chosen individually.

          
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