Breech presentation of the fetus

Pelvic presentation of the fetus is the position of the fetus, which is characterized by the location of the pelvic end of the fetus relative to the plane of entry into the small pelvis.

In pelvic presentations, the fetus is located in the longitudinal position, the pelvic end is required, the head is in the region of the uterine fundus. The frequency of pelvic presentation is 3-3.5% of the total number of births, and in case of premature pregnancy, every fifth birth occurs in a gas presentation.

Pelvic presentation is the usual position of the fetus at the end of the second trimester of pregnancy. But due to the relatively large volume of the pelvic end, in comparison with the head, most of the fruits in the third trimester acquire a head previa.

Causes of pelvic presentation at full term pregnancy can be: polyhydramnios, multinodality, tumors of the uterus and ovaries, decreased muscular tone of the uterus, abnormalities of the uterus, placenta previa, narrow pelvis, fetal development abnormalities.

Most often there is breech presentation - 63-75% of all cases of pelvic presentation. Mixed - 20-24%, foot - 11 - 13%, The position of the fetus with pelvic presentations is the same as for headaches.

[1], [2], [3]

Classification of pelvic presentation

Breech presentation (flexion):

• incomplete or purely gluteal - the buttocks of the fetus are located;
• full or mixed gluteal - the buttocks of the fetus are offered along with the feet;

Leg presentation (extensor:

• incomplete (one foot of the fetus is required);
• complete (both legs of the fetus are offered);
• knee prenatal presentation.

[4], [5], [6], [7]

Diagnosis of pelvic presentations

Diagnosis of pelvic presentations is based mainly on the ability to palpably distinguish the head of the fetus from the buttocks.

When an external obstetric examination is necessary to use the techniques of Leopold:

• at the first reception in the region of the uterus bottom, a round tight ballot head is determined;
• at the third - above the entrance or in the entrance to the small pelvis palpate the irregularly shaped part of the fruit of a soft consistency that does not stand for ballot.

During auscultation, the fetal heartbeat is heard depending on the position on the right or left above the navel. There may be a high standing of the bottom of the uterus.

Diagnosis of pelvic presentation usually causes difficulties with the expressed strain of the muscles of the anterior abdominal wall and increased tone of the uterus, with obesity, double, anencephaly.

When vaginal examination during pregnancy, a voluminous, softish consistency palpable frontal part is palpated through the anterior arch, which differs from the denser and rounded head. 

When internal obstetric examination in childbirth (with the opening of the cervix), palpation of various parts is possible depending on the presentation:

• with breech presentation, palpate the volume soft part of the fetus, define the gluteal hillocks, sacrum, anus, genitals.

Additionally:

• with gluteal incomplete - you can determine the inguinal bend;
• with gluteal full - a foot or two feet, which lie next to the buttocks;
• Gluteal tubercles and anus are located in the same plane;
• with the foot palpable leg, which is distinguished by the signs: the heel bone, the fingers are even, short, the thumb is not diverted and limitedly mobile, not brought to the sole.

Ultrasound is the most informative method of diagnosis. This method allows you to determine not only the pelvic presentation, but also the mass of the fetus, the position of the head (bent, unbent).

The size of the angle between the cervical spine and the occipital bone of the fetus is distinguished by four variants of the position of the head, which is essential for determining the tactics of labor in the case of pelvic presentation:

• the head is bent, the angle is greater than 110; - the head is slightly unbent "" the pose of the military "
• I degree of extension of the head, angle 100-110 °; - the head is moderately unbent
• II degree of extension, angle 90-100 °; - excessive extension of the head, "the fruit looks at the stars"
• III degree of extension of the head, angle less than 90 °.

[8], [9],

The course and management of pregnancy with pelvic presentation

The course of pregnancy in pelvic presentation does not differ from this in headache, but quite often there are complications. The most frequent and unfavorable in its consequences is the early or premature discharge of amniotic fluid. In most cases, this occurs with a legacy presentation.

When conducting labor in a women's consultation, a preliminary diagnosis of pelvic fetal presentation is established in the gestation period of 30 weeks, and the final diagnosis at 37-38 weeks.

In the period of pregnancy 30 weeks. Carry out activities that promote self-rotation of the fetus on the head. For this we recommend:

• position on the side opposite the position of the fetus;
• knee-elbow position for 15 minutes 2-3 times a day.

From 32nd to 37th week, a set of corrective gymnastic exercises is prescribed according to one of the existing techniques (IF Dikan, II Gryshchenko).

Basic elements of corrective gymnastics:

• slopes of the torso of the pregnant woman in the direction of the fetal back;
• flexion of the lower limbs in the knee and hip joints with simultaneous bending of the trunk towards the fetal position;
• arching of the back with an emphasis on the crossbar of the Swedish wall;
• arching of the back in the knee-elbow position;
• flexion of the lower extremities in the knee and hip joints lying on the back, pulling the knees to the abdomen, half-turn of the pelvis with bent limbs towards the position of the fetus.

Contraindications to the gymnastic exercises:

• threat of abortion;
• placenta previa;
• low placenta previa;
• anatomically narrow pelvis of II-III degree.

Taking into account the peculiarities of pregnancy during pelvic presentation of the fetus, at the stage of observation of these pregnant women in the antenatal clinic, the condition of the fetus and the placental complex should be comprehensively assessed using modern diagnostic methods (ultrasound, Doppler, KTG).

External preventive turning of the fetus to the head is not performed in the conditions of the female consultation due to the high risk of complications:

• premature placental abruption;
• outflow of amniotic fluid;
• premature delivery;
• uterine rupture;
• acute distress of the fetus;
• fetal injury.

In case of preservation of pelvic presentation of the fetus in the period of 37-38 weeks. Pregnancy is hospitalized in the obstetric hospital according to the indications:

• the presence of a burdened obstetric-gynecological anamnesis;
• complicated during this pregnancy;
• extragenital pathology:
• the possibility of performing an external rotation of the fetus on the head.

In the case of full-term pregnancy in the hospital of the third level before the onset of labor, it is possible to perform an external turn of the fetus on the head with the informed consent of the pregnant woman. Before the turn, ultrasound is performed, the fetus is evaluated (BPP, if necessary, Doppler), the readiness of the female organism for labor is determined.

External rotation of the fetus on the head

Indications:

• incomplete breech presentation at full term pregnancy and live fetus.

Conditions:

• estimated fetal mass <3700.0 g;
• normal size of the pelvis;
• emptied bladder of a pregnant woman;
• the possibility of performing ultrasound monitoring of the position and condition of the fetus before and after the turn;
• satisfactory condition of the fetus with BPP and the absence of developmental abnormalities;
• normal motor activity of the fetus, sufficient amount of amniotic fluid;
• normal tone of the uterus, a whole fetal bladder;
• readiness of the operating room to provide emergency assistance in case of complications;
• The presence of an experienced qualified specialist who owns the turning technique.

Contraindications:

• complications of the course of pregnancy at the time of making a decision about the external turn (bleeding, distress of the fetus, preeclampsia);
• aggravated obstetric-gynecological history;
• many or little water;
• multiple pregnancies;
• anatomically narrow pelvis;
• presence of cicatricial changes in the vagina or cervix;
• III degree of extension of the head according to ultrasound;
• placenta previa;
• severe extragenital pathology;
• a scar on the uterus, adhesions;
• hydrocephalus and swelling of the fetal neck;
• abnormalities of the uterus;
• tumors of the uterus and appendages.

Technique of external rotation of the fruit on the head:

• position of the woman on its side, with a slope of 30-40 ° toward the back of the fruit;
• buttocks of the fetus are removed from the entrance to the small pelvis by the hands of the doctor, inserted between the womb and the buttocks of the fetus;
• gently move the buttocks of the fetus towards the fetal position:
• shift the head of the fruit in the direction opposite to the position;
• end the turn by moving the head of the fetus to the entrance to the small pelvis, and the buttocks - towards the bottom of the uterus.

If the first turn attempt was unsuccessful, holding the second one would be inappropriate. Taking into account the high percentage of failures of the preventative turnaround, the risk of serious complications, it is necessary to clearly define the indications and contraindications to the rotation.

[10], [11]

The course and management of urgent delivery with pelvic presentation

Features of the course of labor in pelvic presentations are a high risk of possible complications. In the first period of labor, premature and early outpouring of amniotic fluid, loss of small parts of the fetus, umbilical cord, weakness of labor, fetal distress, endometritis in childbirth are possible. In the second period - tilting the fetus handles, rear view, cervical spasm, fetal injury, trauma of the birth canal.

There are three degrees of tilting the handles: I - the handle is in front of the eyelet; II - at the level of the eyelet; III - behind the ear of the fetus. Most often in these cases severe fetal distress occurs as a consequence of prolonged birth of the head.

Particular attention should be paid to the period of expulsion, the improper conduct of which can lead to severe birth injuries or even the death of the fetus.

When giving birth in the pelvic presentation, four stages are distinguished:

1. birth of the fetus before the navel;
2. birth of the fetus to the lower angle of the scapula;
3. the birth of pens;
4. birth of the fetal head.

Biomechanism of childbirth with pelvic presentations of the fetus consists of the following moments;

• the first moment - the insertion and lowering of the buttocks, while their lateral size buttocks are inserted in one of the oblique pelvic dimensions;
• the second moment is the internal turn of the buttocks, which from the wide part move to the narrow part and are set at the bottom of the gas in a straight line, the anterior buttock approaches the pubic symphysis, the posterior to the sacrum;
• the third moment - lateral flexion of the spine in the lumbosacral section. A fixation point is formed between the lower edge of the symphysis and the edge of the ilium of the anterior buttock. The first is the back buttock, and then the anterior. After the birth of the pelvic end, the trunk is straightened, the fetus is born to the navel, then to the lower corner of the scapula, turning backwards;
• the fourth point is the inner turn of the shoulders (the transition from a cross-sectional dimension of a slanting dimension to a straight line), the front shoulder is fixed under the pubic symphysis by the acromial process;
• the fifth moment - lateral flexion of the spine in the cervicothoracic region. The fixation point between the lower edge of the symphysis and the acromial process of the scapula of the fetus. There is a birth of the posterior shoulder, and then the anterior in the direct size of the exit plane from the small pelvis;
• the sixth moment is the internal rotation of the head. The sagittal suture passes into a straight exit size from the small pelvis, the suboccipitary fossa is fixed under the pubis;
• the seventh moment is the bending of the head around the fixation point and its birth.

When leg presentation, the biomechanism of childbirth is the same, only the first of the genital gaps appear not the buttocks, and the legs.

In order to prevent complications in the obstetrical hospital in women in labor with a pelvic presentation of the fetus, it is necessary to determine the plan for the management of labor, that is, after the study individually decide the question of optimal delivery, which depends on:

• age of the pregnant woman;
• term of pregnancy;
• concomitant extragenital and genital pathology;
• obstetric complications;
• readiness of the mother's organism for childbirth;
• pelvic dimensions;
• condition of the fetus, its mass and sex;
• varieties of pelvic presentation;
• degree of extension of the fetal head.

To favorable obstetric situations, in which labor can be conducted through natural birth canals, include:

• satisfactory condition of the pregnant and fetus;
• complete ratio of pelvis to mother and fetus;
• sufficient biological readiness of the mother's organism for childbirth;
• the presence of a purely gluteal or mixed breech presentation;
• the bent head of the fetus.

With conservative management of labor, it is necessary:

• assess the testimony, make sure that there are all the necessary conditions for safe delivery through the natural birth canal, and there are no indications for caesarean section;
• follow the progress of the first period of labor by maintaining the partograph, registering CTG for 15 minutes every 2 hours;
• in the case of rupture of the membranes, an internal obstetrical examination should be urgently performed to exclude the prolapse of the umbilical cord;
• the second period of labor should be conducted with a mobilized vein for intravenous administration of 5 DB oxytocin in 500 ml isotonic sodium chloride solution (up to 20 drops per 1 min) in the presence of an anesthesiologist and a neonatologist;
• carrying out an episiotomy according to the indications (if the crotch does not stretch well); underpudal anesthesia (C).

The planned caesarean section is performed according to the following indications:

• expected fetal body weight 3700 g and more;
• leg presentation of the fetus;
• extensor head III degree according to ultrasound;
• tumor of the fetal neck and hydrocephalus.

The technique of caesarean section and methods of anesthesia for pelvic presentation of the fetus do not differ from those with head presentations. The fetus is extracted for an inguinal bend (purely gluteal presentation) or for the leg that lies in front. The head is removed using manipulations reminiscent of the techniques of Moriso-Levre-Lachapelle.