Lecture of the butt in obstetrics

2021-03-20 12:00 AM

During the first two trimesters of pregnancy, the fetal head is larger than the buttocks, so reincarnation is usually located at the bottom of the uterus. In the third quarter, the fetal buttocks grow faster and are larger than the head

General perception

The buttock is a longitudinal position with the tip at the base of the uterus, the buttocks at the cervix, and the buttocks present before the upper waist during labor.

The buttocks have the ability to lay sugars but are susceptible to the tail, so some authors consider it a difficult birth.

Percentage of buttocks accounts for 3 - 4%.


One can be divided into 2 basic categories.

Full buttock or full buttock: is a fetus consisting of all the buttocks and legs of the fetus folded, so it looks like the fetus squatting or sitting cross-legged in the uterus, is a common type of buttock.

An incomplete buttock or a missing butt: is a person that is present in front of the upper waist or has only the buttocks or legs or the hips.

The buttocks lack the butt type: only the buttocks are present in front of the upper waist, the legs stretched out straight up the fetal side.

The butt is burning and arrogant: imagined as a fetus kneeling in the womb.

The buttocks lack the leg type: during labor examination, we can see the reincarnation at the base of the uterus, but inside the uterine cavity only feels one or both of the fetal feet without seeing the buttocks.

The buttocks that lack the leg or knee type during childbirth will turn into a secondary full butt.

The landmark of the buttock: is the tip of the sacrum.

The diameter of the rump: is the diameter of the thigh mound: 9.5 cm is the smallest diameter in the fetuses. Therefore, when laying the buttocks of the buttocks is very easy to give birth, but when the first is born, it is easy to get the posterior head.

The world and the like:

So: the pineal mold of the buttocks is on the same side as the back, so if you can see the back of the fetus on the other side, then the buttocks are on that side.

Type of position: there are 4 types of buttress:

Same left pots, abbreviated CgCTT.

Same left pots, abbreviated CgCTS.

The same pot must first, abbreviated CgCFT.

The same pot must follow, abbreviated CgCFS.

The butt has two types of books:

Same horizontal left pots, abbreviated CgCTN.

The same pot must be horizontal, abbreviated CgCFN.


According to Pajot's corrective rule, the shape of the fetus in the uterus must match the shape inside the uterus. During the first two trimesters of pregnancy, the fetal head is larger than the buttocks, so the reincarnation is usually located at the bottom of the uterus. In the third quarter, the fetal buttocks grow faster and bigger than the head, so the reincarnation usually turns down the cervix so that the fetal buttocks are facing the bottom of the uterus in accordance with the width of the uterine base. Therefore, the rate of buttocks in preterm pregnancy is higher than that of full term from 1/30 - 1/60, sometimes up to 1/100.

By fetus

Big head, hydrocephalus.

2nd pregnancy of twins; malnourished pregnancy.

Due to the fetal appendage

Vegetable forwards.

Poly amniotic fluid or minimal amniotic fluid.

Vegetable cord is short or is caused by a string of vegetables wrapped around the neck.

By mother

The small uterus is difficult to correct in a woman who has had a labor many times.

An abnormal shape in the uterus such as a malformed uterus, a double uterus, a biconcave, cylindrical, two uterus, a uterus with fibrous nucleus, the uterus is squeezed from the outside by an ovarian cyst.

Pregnant women have a narrow pelvis.

Symptoms and diagnosis during pregnancy


Question: Pregnant woman feels the fetus is stepping on the lower part of the navel, but when the fetus moves strongly, she reincarnates or pushes on the right lower rib.

See: see death. the uterus is ovate or cylindrical, the uterus is tilted to the right.

Manipulation of the hypotenic region does not see the equilateral pole of the head. Manipulation only sees an uneven mass in a solid, soft spot, if there is a lot of amniotic fluid, there is no sign of bobbing as in the cot. From there, manipulating the bottom of the uterus is an area of ​​the back of the fetus. If the buttock is in the front posture, the buttock is more visible than the posterior posture. On the contrary, if it is the posterior position, facing the back, there is a feeling of a lumpy feeling of the fetal limb. Manipulation near the base of the uterus or on one side of the uterine horn can see a firm round mass of the fetal head. need to look for signs of "shaking of fetal head" if present, it can be sure it is the fetal head. The bottom groove can be seen between the back and the head.

Hearing: The fetal heart socket is usually found high above the navel.

Internal visit: because cervical labor has not yet been closed. Visiting the pocket with us does not feel that there is a solid round mass, but a soft and often high mass suggesting the buttock, sometimes there is a feeling of being accompanied by a small mass suggesting the buttock.


Clinical diagnosis:

The signs found by the clinical diagnosis remind us of the buttocks. To determine, it is necessary to base on subclinical signs.

Subclinical diagnosis:

Ultrasound: is a valuable subclinical method in diagnosis as well as prognosis can evaluate the position of the head, back, buttocks, measuring fetal diameters (bipolar, abdominal diameter, length femur), amniotic fluid, clingy site. Determine the weight of the fetus, thereby giving more accurate management and prognosis.

X-ray: is a method currently rarely used, only applied in medical facilities that do not have an ultrasound machine, but can assess the condition of the pelvis, determine where the fetus is bowed or not good and can play shows some abnormalities of the musculoskeletal system.

Scanner: can measure the diameter of the pelvis, the diameter of the fetus.

Implementing the quadrants

Need based on clinical signs, subclinical. Special time, should only be determined by the leg in the last month of pregnancy or before labor, because at this time the fetus has no time to spin.

Diagnosis and management during labor



Usually not clear can see the fetus kick in the umbilical region, pain in the lower ribs (usually right because the reincarnation presses on the liver).


You can see a cylindrical uterus.

Lower uterine manipulation does not see the tip is round, solid, only see an irregular mass, large soft spot. Sometimes it is difficult to define parts of the fetus because of uterine contractions.

Hear: fetal heart is at the level of the umbilical level because the fetus is down.

Visit in:

When the cervix is ​​open, the amniotic fluid remains remaining, avoiding rupture of the amniotic fluid on examination; through the amniotic membrane may feel:

If you feel your baby's buttocks and one or both feet, think about the buttock.

If you see the buttock mass, it is possible that the buttock is missing.

If only the fetal leg is found, the buttocks may be missing.

During internal examination, it is necessary to determine whether there is a vegetable cord in the amniotic sac or not?

Visiting while the cervix is ​​open and the amniotic sac has completely ruptured is easier to examine.

If you see the sacrum, anus hole between the buttocks, the genitals of the fetus and the fetal foot, we can easily diagnose the buttock.

If there is only the feeling of the sacrum, the anus in the middle of the fetal buttocks needs to differentiate:

The face: for having a mouth between the cheeks.

If fetal buttocks and feet are felt, a differential diagnosis should be made with:

Capricorn: distinguishing legs and hands of the fetus based on the anatomical structure as follows:

Thumb: the thumb smaller and further away from the other finger, and the big toe larger and closer to the other fingers. The long, folded fingers have an inverted V-shape and do not have heels so they can pull out a ladder.

Identify the foot: toes short, five toes aligned and almost in line, the foot can be angled at the angle of the shin because of the heel.

When visiting, need to determine whether there is a vegetable wire in the amniotic sac or not?


Diagnose the buttock during labor because the cervix is ​​open. However, sometimes it is also necessary to have an ultrasound or radiograph to determine the pinnacle.

Differential diagnosis

The crown: the buttock lacks the buttock type, especially when the amniotic fluid is not broken. On external examination in the hypotenic region in the buttocks lacking, there is also a feeling of small and solid like the head of the fetus, but on internal examination, hair, posterior posterior and longitudinal joint line of the crown cannot be found.

The base of the cot: may be confused with the buttocks enough when only one leg is palpable. Because the fetal head is easily confused with fetal buttocks in babies with little hair.

The face: when the face of the amniotic fluid has broken, the fetal cheeks are bent-mold, so it is easy to confuse the buttocks, and the fetal mouth is easy to confuse with the anus of the buttocks.

Horizontal throne: the fetal buttocks are but the fetal head is in the lower right flank of the fetus in the left iliac fossa, so on external examination it is easy to confuse the horizontal throne.

Prognostic factors for buttock birth

Pregnancy factor

Pregnancy: the buttocks lack the buttock type has a better prognosis than the buttocks.

Primary buttock head can be detected clinically or can be determined by X-ray.

The buttock has a big head, hydrocephalus.

The second butt of the twin.

Fetal weight.

The mother factor

Age and number of births.

Obstetric history.

Limited pots.

The uterus has an old surgical scar.

Abnormalities in the uterus, uterine malformations (uterus with septum, bipedal uterus, vaginal septum, uterine fibroids ...)

Factor of fetal appendage

Amniotic fluid.

Vegetable salad.

Vegetable forwards.


Evaluation of clotting factors in labor

Pregnancy: the best fetal cardiac and contraceptive based monitoring machine.

Uterine contractions: the driving force of labor, in the buttocks, uterine contractions play an important role, especially in the period of pregnancy. If the contractions are not rhythmically regular, it will become difficult.

Election of the cervix: based on the flow chart.

Progression of the fetus.

Mechanism to throne enough

Different from the first person where the birth took place:

The buttocks - shoulders and head. Each section has its own mechanism with 4 periods: falling, descending and rotating, the book of the diameter of the throne gradually increases: the amphibian sits 9cm, the shoulder dip is reduced to 9.5cm, the dipole is 9.5cm, the hardest part ( last comparison).


Potential: the throne will fall under the diameter of the thigh bifurcum following the diagonal diameter of the pelvis, there is no phenomenon of shrinking because it is small enough and falls easily.

Usually fall symmetrical, when the diameter of the thigh bipolar to the upper waist falls easily and early with the buttocks lacking in the buttock, more slowly in the buttocks completely.

Down and turn: rotating 45 ° to become CgCTN or CgCFN rotated and down often simultaneously. The diameter of the thigh bipolar will follow the anterior and posterior diameter of the lower waist, the throne resting on the perineal layer.

Book: when the posterior rump comes down the anterior rump, the anterior buttocks and the fore legs of the anterior seat. Once the buttocks have crossed the lower edge of the joint, keep them in place so that the hind legs and the posterior buttocks will extend out. That way, the buttocks are delivered to the womb, then the fetus will expel and to the stage of giving birth.

Drop: the head to reach the head must bow well, ie the chin must rest close to the sternum, so it is necessary to have the help of the midwife from the abdomen. Diameter of anterior foramen passes along the left diagonal diameter of the pelvis (ie diameter of the apical diploid passing along the right diagonal diameter of the pelvis).

Down and rotate: the diameter of the fetus according to any diameter will also descend along that plane of the pelvis. After descending, the head will rotate 45 ° to let the occipital fall under the joint and fixed there so that the fetus head next to the rear end.

Ledger: the posterior head book begins to run from: lower occipital - hold, lower occipital - mouth, lower occipital, lower occipital - forehead and finally to lower occipital - anterior occipital. The process of fast post-posterior registration does not need to be molded, so the fetal buttocks are rounded.

Missing breech birth mechanism

Similar to the inferiority of the buttock, the effects of uterine contractions and the woman's strength are the following:


The missing butt is smaller than the buttock, so it falls more easily than the full butt. After laying the buttocks to the shoulder, the abdomen, the fetal legs are still straight and stretched in front of the shoulders, along with the fetus's entire spine into a longitudinal, ovoid-like mass that does not bend along the axis of the subframe, so this stage pull long and we must not lower the fetal's legs.


The diameter of the shoulder dip also slips down and rotates like the diameter of the thigh bipolar. During the period of childbirth usually lasts because the back of the fetus does not bend with the curvature of the frame. The lack of shoulder rests in the buttocks due to the fact that the legs are stretched straight up and down the shoulders, the fetus cannot raise his arms to his head and also loses his looking under the chin, making the queen unable to face up, now is also the time of the neck bow and vagina are maximized in preparation for a posterior regimen.


The rear end of the burnt throne often bowed well. Under the pressure of the uterine contraction, the mother's tension and the support for the woman's head to bow well make the posterior to flow less difficult than the posterior birth of the buttocks.

Some difficult cases in the delivery mechanism

The throne does not fall: often in the buttocks enough, the throne does not fall due to that type.

Difficulties caused by raising hands: often caused by physicians (push too soon, pull the fetus, this abdomen is not right at the right time).

Sometimes it is due to a mismatch of the fetus and pelvis without knowing it in advance.

Head end. This is a very serious cause that can cause trauma to the fetus, even death of the fetus.

Head cannot fall due to the posture, due to fetal mismatch - pelvic area, head is not bowed well, because the back is turned back.

Narrow middle waist.

Due to software: due to fast delivery, the perineal layer is not well prepared, it can cause the posterior terminal to cause severe fetal injury if the intervention is violent.

Direction of treatment

During pregnancy

Once the buttock is diagnosed, it is necessary to examine and carry out the necessary investigations to assess the risk (ultrasound, X-ray, Scanner).

The foreign turns pregnant into the crown before. Currently, no. Many authors do not agree with external rotation because there are many rare risks for the fetus. If done, should do at a facility capable of surgery, follow up under ultrasound of the fetus for 35- 36 weeks, do not do with uterus deformity, uterus with old abutment scars, forward vegetables, vegetable cord wrap neck (diagnosed by ultrasound), narrow, flat, distorted pelvis ...

Accidents: vegetable peeling, causing fetal death, dangerous mother's life.

If not, what to do? It is necessary to fully implement factors to evaluate fetal prognosis to see if there is a possibility of inferior or upper fertility (see prognostic factors for breech birth).

If there is a possibility of infertility, wait for labor to further assess the dynamic factors: uterine contraction, erection of the uterus, amniotic fluid and amniotic fluid, fetal condition, fetal permeability and condition. mother.

If not able to deliver lower sugar, then wait for labor and take initiative by cesarean section when the conditions are met.

During natural labor

Indications for cesarean section at the onset of labor:

Abnormal, narrow, skewed, flat pelvis.

Mother's age: children compared to older.

Primary fetus, head back.

A history of severe obstetrics, infertility treatment, old surgical scarring uterus, anterior tumor (fibroids, ovarian cysts).

The relative surgical indications in labor:

The buttocks + the calf + the fetus are> 3000g or the buttocks + the premature rupture of the amniotic fluid.

The buttocks + the vegetable chain inside or outside the rancid wrap.

The buttock + cervix progresses slowly.

The buttocks + mother have medical problems (heart disease, high blood pressure).

A pregnant buttock.

Track bottom line laying

Track contractions, erase and open the neck of the chest:

Need to adjust uterine contractions rhythmically, regularly, if the contractions are adjusted with drugs. When the contraction is not effective enough, it is necessary to infuse oxytocin intravenously. Limit internal examination, keep the amniotic sac until the cervix is ​​completely open. When the amniotic fluid breaks in the amniotic fluid, there is usually su stool, but this is not a sign of fetal failure, it is necessary to monitor the fetal heart condition.

Monitor the mother's condition during oxytocin infusion.

Delivery in the buttocks according to the natural method:

Currently, oxytocin infusion set out in all cases to correct uterine contractions well, instructing women to push during uterine contractions, not much interfering with the fetus.

The presence of a neonatal physician is essential.

We can apply a number of measures to help deliver buttocks:

Tschovianov method: the purpose of making the throne fall into the subframe slowly dilates the uterus, vagina and episiotomy to create favorable conditions. The midwifery must keep the throne from going out for a certain period of time.

Lack of buttocks: because the legs fold up and form a mass will make her uterus, vagina and rectum expand well.

Some people need to use drugs to have strong contractions, instruct women to squeeze and press the head on top of the pubic joint in combination.

Systemic exhaustion of pregnancy with glucose and oxygen because according to the authors in the buttocks it is susceptible to pregnancy failure.

For the buttocks enough: avoid walking a lot, keep the amniotic fluid from breaking prematurely. When the throne protrudes the vulva, the midwife must use a large gauze (chancre) to press on the vulva every time there is a contraction to let the buttocks out of the book, the buttocks and fetal body will dilate the cervix to make the uterus. fully open, dilate the vagina and episodic layer to help reincarnation after the goat is easy, holding time from 10-20 minutes (pay attention to loosen the vegetable strings when the abdomen is numbered). Close monitoring of fetal heart when there are signs of fetal failure need to give the fetus immediately. When preparing the head, you can inject 2 units of oxytocin + 2 ampoules of atropin l / 4mg (vein) and press on the pubic bone to help the head bow, helping to deliver fast.

For buttocks lacking butt type: just like in buttocks completely, try to keep my butt. When the buttocks are exposed because the legs and buttocks are well open to the vagina and epithelium, the midwife hugging the fetal thigh, two thumbs behind the thighs, the other fingers toward the bone and facing the fetus upwards, holding the fetus. The fetal body is always pressed against the abdomen and chest, this causes the breast and leg mass to dilate more softly, pointing the buttocks up on the sole in case of loss. When the first number is also used to increase the shrinkage to help the head better. The head can be numbered according to the Bracht or Mauriceau method.

Procedures commonly used in buttock support

The following tips:

Bracht procedure: when the body and arms are out, the midwife holds the fetus with both hands by holding the thumbs on the front of the thigh and holding the legs of the fetus and then by a coordinated gesture forward, up on and turn the fetus on the womb. Do not pull anything into the fetus.

Upper head with Forceps: When the head is held in the genital tract, íorceps can be easily removed by: the fetus is held on the leg and raised by a woman, the main supporter puts the two torceps along. arrogant, at first pulled downwards and then pulled and lifted the people.

Mauriceau trick: applied when the back end is not low. This procedure can easily damage the fetal arm or mouth tangles.


Makes the head bow better.

Pull the head down in the subframe.

Turn the head to the satellites.

Pull and tilt for the top of the window.

How to do it: Have the fetus ride on the deliverer's forearms - bring the middle and index fingers into the fetal mouth all the way to the bottom of the tongue and press down so the chin is close to the chest to help the fetus bend. The other hand is on the back, close to the shoulder, push the fingers into the occipital region to coordinate with the hand inside to make the head bow. Then use the outer fingers to embrace the shoulders and the index finger slit and the middle and to embrace the nape of the fetus and coordinate with the inner hand to perform the following operations: pull the fetus down, bring the head to the occipital and bring the fetus forward and flip upwards. mother's womb.

Open the head by folding the head close to the fetal chest and belly up towards the womb.

The lowering of the hand (the Loveseat procedure) is the least traumatic and most effective procedure. When supporting the buttock, when the fetus has reached the shoulder, the midwife needs to put the finger up to check if the hand of the fetus is raised or not.

Then turn 180 ° in the opposite direction to bring the back arm forward, the elbow will appear in the vulva. Next, the fetus will be lowered to fix the dot below the joint to the number one.

The Butt-Tromectomy: is the procedure whereby the physician puts his hand in the genital tract and pulls the fetus out according to the delivery mechanism in order to remove the pregnancy early. Very few are indicated today due to the high risk of pregnancy and postpartum mortality.