Childbirth

The birth of is called expulsion from the uterus of the fetus and after - the child's place, membranes, umbilical cord. Normal births usually occur after 40 weeks of pregnancy and are called urgent. At an earlier birth the child is called premature.

The weight of a full-term child is more than 2800 grams. Children weighing 2500 grams or less are considered premature, although they in most cases develop well.

By the time of delivery, the uterus is a pear-shaped muscular organ. The fruit is in a fetal bladder filled with amniotic fluid. The amount of water usually varies from 0.5 to 1.5 liters. The body of the uterus has a powerfully developed musculature. It is the most active part of the uterus during childbirth. The cervix located below has a thinner layer of musculature. The fetus in the uterus is usually head down, which is explained by the greater severity of the head compared to other parts of the body.

Normal position of the fetus in the uterus is also considered the location of his pelvic end down( pelvic presentation).There is this arrangement of the fetus in 3.5% of births. It often occurs in women giving birth, as well as with premature birth.

Nutrients and oxygen fetus gets from the mother's blood through the baby's place( placenta).

In appearance, the placenta is similar to a rounded thick cake. By the time of birth, the diameter of the placenta reaches 15-18 centimeters, thickness - 2-3 centimeters, weight - 500 grams.

The fetus is connected to the placenta by the umbilical cord( umbilical cord).Blood vessels pass through it, through which the mother's blood flows from the placenta to the fetus and blood flows back to the mother. The length of the umbilical cord is about 50 centimeters, the average thickness is 1.5 centimeters.

Sometimes the uterus develops not one, but several fruits, more often two - twins. Pregnancy with two and more fruits is called multiplane, while children born in multiple pregnancies are called twins. The birth of twins occurs on average once per 70-80 births.

Multiple pregnancy can result from the fertilization of two or more simultaneously maturing eggs or from one fertilized egg as a result of a special crushing of it. Each of the developing fetuses, as a rule, has its own fetal bladder at one common placenta or in the presence of a different placenta.

What causes the onset of labor - contractions of the uterus in order to expel the fetus? This condition is favored by changes in the activity of the endocrine glands, in the state of the nervous system, and the increasing effect on the uterus of various stimuli, both produced in the body and coming from the fetal side. In the last weeks of pregnancy there is a decrease in the number of amniotic fluid and a more intimate fetal coverage of the uterine walls.

In addition to preparing for labor, in the body of a pregnant woman at the time of birth, changes take place that play the role of protective factors, blood coagulability increases, its total number increases, and the biochemical composition of the blood changes.

At the end of pregnancy, some women note at times the sensation of a pulling character in the sacrum. These sensations are explained by the blurred contractions of the uterus. However, even these unobtrusive abbreviations nevertheless lead to stretching of the walls of the lower part of the uterus and contribute to the lowering of the fetal head. Dropping, the head puts pressure on the walls of the uterus, causing a new irritation for them.

At the onset of labor, rare, short-lived, but regular contractions occur. Generic activity occurs more often at night, during sleep. This feature of the birth act depends on specific changes in the central

nervous system in pregnant women before delivery. As the labor activity develops, the bouts become longer and come on through shorter intervals. With developed labor activity, contractions last for 40-50 seconds and occur every 2-3 minutes.

Part of women in the process of childbirth have abnormalities in contraction of the uterus. More often they are weakened - they come through more sparse intervals of time and with less duration. Less often contractions take a convulsive character. Disorders of labor often lead to the pathological course of the birth act, increasing the death rate of children and the incidence of mothers in the postpartum period.

The cause of abnormal rhythm of uterine contractions is usually the underdevelopment of the reproductive system or the entire body of a woman, fatigue in the long course of the birth act, as well as the increased excitability of the nervous system of a woman during childbirth. The excitement of the woman in labor creates the prerequisites for the painful course of the birth act. Anesthesia performed in such women is often ineffective.

With pregnant women with an unstable nervous system, especially with primiparous, it is necessary during pregnancy especially carefully to conduct in the women's consultation psycho-preventive preparation for childbirth.

The fetus, passing through the soft generic pathways( uterus, vagina), must pass through the bone pelvis. The head of the fetus passes first with the headache. In a normally developed woman, the pelvis has such dimensions that allow the head of the full-term fetus to pass through the bone ring without much difficulty.

In addition, the fetal head has the ability to change its shape under the influence of the pressure of the uterine walls during the birth act. This makes it easier to pass it through the birth canal. The elasticity of the head is due to the special construction of the bones of the skull: the thin bones of the skull are interconnected by means of membranes. The membranes are called sutures and fontanelles. Changing the shape of the head during labor is temporary;a few days after birth, it is again rounded.

Passage of the fetus through the birth canal takes quite a long time: for women giving birth for the first time, the labor lasts on average 16-20 hours, for those who give birth to repeat-

but, -7-12 hours. This circumstance has a positive effect on the outcome of childbirth. Rapid births are harmful to the child, as well as excessively long. As a result of the peculiarities of the structure of the birth canal, childbirth proceeds gradually and rhythmically, which is most favorable for the child and mother.

The first obstacle to fetal movement is the cervix, which is outside pregnancy in most women is closed. By the end of pregnancy, due to the loosening of the tissues, the neck becomes more extensible. To pass the fetus, it is necessary that the cervix is ​​fully opened. In primiparous women, the cervix of the uterus under the pressure of the fetal egg first becomes thinner( smoothed out), and then it opens.

The walls of the vagina are well stretchable, and therefore the obstructions to passage of the fetus do not represent. Shortly before the birth of the fetal head, it is necessary to overcome the resistance of the perineal muscles( pelvic floor muscles).The obstetricians try to "remove" the head slowly, so that the perineal tissues can stretch as far as possible. It takes usually 20-30 minutes to remove the head. Sometimes, despite all the precautions of the receiving delivery, even with quite normal births, there are still tears and tears in the tissues. They restore by suturing. Violation of the integrity of the crotch or vagina occurs more often in parturient women who do not comply with the prescription of a doctor or midwife, as well as in women who have intractable tissues or scars after former births.

Births are divided into three periods: the first - the period of disclosure, the second - the period of expulsion of the fetus, the third - consecutive.

In the first period, the neck opens. The duration of the first period of labor is, on average, 14-17 hours at the first birth and 6-9 hours with repeated labor.

The second period of labor, the so-called fetal expulsion period, begins with the moment of full disclosure of the cervix. In this period, contractions of the uterus - fights - are joined by abdominal contractions, there are attempts. In one of the attempts, the membranes of the fetal bladder burst and the outflow of amniotic fluid occurs. Exercises arise involuntarily, as a response to the pressure of the head on the walls of the vagina, but the parturient can still partially suppress them with willpower. She can, in addition, force herself to push herself out of the bout. The duration of the effort depends on the development of labor.

The period of exile in primiparas lasts approximately 2-3 hours, in re-birth-0.5-1 hour.

It is based on the regulation of labor activity on the possibility of a woman in labor to suppress to some extent the strength of attempts. Due to this, you can slow down the movement of the head and "take it out" at the most convenient time. In obstetrics, such interference in the course of the generic act is called birth control.

Usually the fetus lies in the uterus in the longitudinal position. The lowest lying part of it is the head, and usually it is bent. The occiput and the back of the fetus can be turned more often to one of the lateral walls of the uterus. When the second period of labor begins, the head bends even more. Moving along the mother's birth canals, the fetus starts to make rotational movements at the same time, and when the head reaches the exit from the pelvic canal, its occipital is turned anteriorly. Then the back of the head rests against the mother's pelvic articulation, and, gradually unbending, the head begins to scratch first and then erupt. With this mechanism of birth the head passes through the pelvis of the mother with its smallest circumference. The position of the fetus with the head down is most favorable for both the mother and the fetus.

Following the head a trunk is born. Due to the preliminary stretching of the entrance to the vagina by the most voluminous part of the fetus - the head - the shoulders pass almost without difficulty. The rest of the trunk is usually born even easier.

In pelvic presentation at first, buttocks are born, the head is born last.

After the birth of the fetus, the third stage of labor comes - the consecutive one. It lasts from the moment of the birth of the child to the separation of the afterbirth. Separation and excretion of the afterbirth is usually accompanied by small recurrent contractions of the uterus. To isolate the outward outward, the parturient woman usually has to push. During the expulsion of the afterburn, there is a small blood loss, often not exceeding 200 milliliters.

After the release of the afterbirth, the postpartum period begins.

The peculiarities of the course of labor, as well as their outcome, depend to some extent on the mothers: from her behavior during the birth act, the accuracy of the instructions of the doctor, etc. The woman must take an active part in the generic process.