Morphological and physiological features of the fetus in different periods of intrauterine life. The main signs of a full-term newborn: description and features The criterion for fetal maturity is not

Fertilization occurs in the ampullary section of the tube after the processes of capacitation of spermatozoa - the loss of surface glycoprotein antigens of the spermatozoon head and its activation. Capacitation occurs in the vagina, uterus, tubes as sperm advance.

A necessary condition for fertilization is the synchrony of gametogenesis and ovulation. The time between ovulation and fertilization in women ranges from 12-24 hours. Of the 100 ovulated eggs, 15 are not fertilized (physiological prezygous elimination).

Statistical analysis of childbirth in the countries of the USA, Western Europe and Australia showed that there are characteristic fertility curves with a wide peak in the winter months, a slight rise in summer and a decrease in spring and autumn. And conception often occurs in spring and autumn, in winter and summer anovulatory and hypoluteal cycles are more often observed. Seasonal variation in the frequency of certain types of congenital pathology in humans is explained by the desynchronization of ovulation and the process of maturation of the oocyte during the transition from anovulatory cycles to ovulatory cycles during the change of seasons of the year (Nikitin A.I. Aging of gametes and congenital pathology // Obstetrics and Gynecology. - 1981. - Nos. 3, 6-9).

The rhythm of gametogenesis and ovulation is determined by the duration of light stimulation. In Arkhangelsk, the minimum daylight hours are 3 hours 51 minutes (December 22), the maximum is 21 hours 21 minutes (June 22). The mediated action of light through the pineal gland causes 80-85% of the appearance of menarche in the first quarter of the year.

And pregnancy proceeds most favorably at conception with increasing daylight hours from 7 to 14 hours (February 10 - April 15) or decreasing daylight hours from 2 to 7 hours (August 15 - November 15). At the same time, for primiparous women under the age of 24, the optimal period of conception is the first peak of fertility, which corresponds to the menarche according to the season - the cumulation of fertility. For women over 28 years of age, the second seasonal peak of fertility is more optimal.

When conceived during favorable periods of fertility, the frequency of such pregnancy complications as miscarriage, early and late toxicosis decreases by 2-2.5 times.

Critical periods of pregnancy development

Fertilization (40 hours)	Embryogenesis (up to 9 weeks):	zygote-morula
implantation (1-2 weeks)		blastula
placentation (3-6 - 12-14 weeks)	histoorganogenesis (up to 12-14 weeks)
	fetogenesis:	functional genesis (up to 18-24 weeks)
		intensive fetal growth systemogenesis (up to 37 weeks)
		childbirth

Up to 50% of zygotes die in the early stages of development and about 20% of diagnosed pregnancies end in spontaneous miscarriage, with more than half of them due to lethal chromosome anomalies.

Artificial termination of pregnancy causes a sudden and fundamentally different reaction from spontaneous abortion. Therefore, after an artificial abortion, the frequency of intrauterine death of embryos, mostly male, increases in subsequent pregnancies.

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The processes of implantation, placentation depend on the decidual reaction of the endometrium. The active function of the placenta is formed by 14-16 weeks, by the end of pregnancy the contact area of the placental villi is 8-12 m 3 . The placenta is the functional heart of pregnancy. The total blood flow in the intervillous space is 500-600 ml/min. Blood circulation in the intervillous space occurs slowly at low pressure (10 mm Hg), due to which an effective metabolism is carried out, and venous blood is discharged through the marginal sinus into the uterine veins. The placenta performs the function of external respiration, excretory, nutritional, synthesis of fetal proteins, depositing, intrasecretory (synthesis of chorionic gonadotropin, sex steroid hormones, relaxin, placental lactogen, trophoblastic b 1 -glycoprotein - TBG, a 2 - fertility microglobulin - AMHF, placental - a 1 - microglobulin - PAMG-1).

Alpha fetoprotein (AFP) is an embryo-specific protein in the amniotic fluid, its increase is observed with abnormalities in the development of the neural tube, congenital nephrosis, teratomas, gastrointestinal atresia, Turner, Down, Meckel syndromes, Fallot's tetralogy, etc., as well as intrauterine fetal death.

Trophoblastic beta globulin (TBG) appears from the end of the first week of pregnancy (possibility early diagnosis), increases as pregnancy increases. Its decrease is observed in non-developing pregnancy, moderate and severe preeclampsia and miscarriage.

human placental lactogen (PLC) begins to be determined from the 18-20th week of pregnancy. Its level decreases with gestosis, the threat of abortion, intrauterine fetal hypotrophy. Its low content before delivery predicts complications in childbirth and the postpartum period, intranatal fetal asphyxia.

Fertility Alpha-2 Microglobulin (AMHF) is secreted into the amniotic fluid. Specific outside of pregnancy for ovulation with a maximum increase towards the end of the cycle.

Placental alpha-1 microglobulin (PAMG-1) is found in amniotic fluid, decreases as pregnancy progresses. It is related to the processes of regulation of fetal growth. With gestosis, the threat of abortion, hypotrophy, there is a significant increase in the serum concentration of PAMG-1.

The placenta provides immune protection for the embryo and fetus, fixing antibodies and reducing the mother's cellular and tissue immunity, its histagematical barrier regulates the penetration of substances from mother to fetus and vice versa.

The placental permeability index for medicinal substances averages 50%, with wide fluctuations from 10 to 90-100%.

There is also a paraplacental exchange, due to the active function of the decidua, amniotic and chorionic membranes. Amniotic fluid is formed by the epithelium of the amnion, and their average daily exchange is 12-15 liters. The amnion and chorion contain enzymes of nitrogen, carbohydrate and lipid metabolism, RNA, glycogen, mucopolysaccharides, proteins and amino acids. Glucose, urea, potassium, sodium, calcium pass freely through the amnion and chorion.

Indicators physical development fetus depending on gestational age

Pregnancy period, weeks	Fruit weight, g	Fetal growth, cm
12	40	8-9
16	120	16
20	300-320	24-26
24	500-600	28-31
28	1000	35
32	1600-1800	40-42
36	2500-2750	45-48
40	3500	50

For 10 lunar months, there is an increase in the mass of the fetus compared to the mass of the zygote in 6 ´ 10 12 times.

Cumulative signs of fetal maturity

Height 48-50 cm, weight 3200-3500 g.

The chest is convex, the umbilical ring is between the womb and the navel.

The skin is pale pink, smooth, smooth, the subcutaneous layer is pronounced, the remains of a cheese-like lubricant in the skin folds, vellus hair on the shoulders and upper back, the nails go beyond the fingertips, the hair on the head is up to 2 cm.

The ear and nasal cartilages are elastic.

The testicles are in the scrotum, the clitoris and labia minora are covered with large ones.

The movements are active, the eyes are open, the cry is loud, it takes the breast well.

Principles of a systematic approach to the study of the relationship between mother and fetus

The fetal-maternal relationship proceeds in an inseparable unity, while not so much the fetus adapts to its external environment (mother), as the external environment itself is purposefully restructured for the optimal implementation of conditions that can ensure the most complete realization of genetic capabilities. The functional system mother-placenta-fetus is formed.

Systemogenesis is the selective development in embryogenesis of structures that differ in function and localization, which, when combined, form functional systems that provide vital manifestations of a developing organism.

The development of a certain organ of the fetus depends on the state of this organ of the mother.

Biophysical profile of the fetus ( A.M. Vintrilers, 1983)

Non-stress test (NST)

Fetal respiratory movements (FRP)

2 b.	-	at least one episode of DDP lasting 60 seconds. and more in 30 min. observations
1 b.	-	at least one episode of DDP from 30 to 60 sec. in 30 min. observations
0 b.	-	DDP less than 30 sec. or their absence in 30 minutes. observations
Fetal activity (YES)
2 b.	-	at least 3 generalized movements in 30 minutes. observations
1 b.	-	1-2 generalized movements in 30 minutes. observations
0 b.	-	absence of generalized movements in 30 minutes. observations
When comparing the mother's feelings about the movement of the fetus with ultrasound data, the coincidence is 80-85%. Fetal movements are more intense in the evening, an increase in their number occurs from 20 to 32 weeks of pregnancy, in the last 2 months of pregnancy, the number of fetal movements decreases. A decrease in the intensity of movements in violation of the condition of the fetus occurs 12-96 hours earlier than changes in the ECG of the fetus.
Fetal tone (TP)
2 b.	-	one episode or more of extension with a return to the flexion position of the spine and limbs in 30 minutes.
1 b.	-	at least one episode of extension with a return to flexion of either the limbs or the spine.
0 b.	-	limbs in flexed position
Volume amniotic fluid(OOB)
2 b.	-	water is clearly defined in the uterus, the vertical diameter of the free area of water is 2 cm or more
1 b.	-	vertical diameter of the free area of water 1-2 cm
0 b.	-	close arrangement of small parts of the fruit, the vertical diameter of the free area of water is less than 1 cm
The degree of maturity of the placenta (FFP) - according to P.A. Urannum, 1979
2 b.	-	0, I, II maturity of the placenta
1 b.	-	placenta on the posterior wall of the uterus and it is difficult to determine the degree of maturity
0 b.	-	III maturity of the placenta

The last two weeks of pregnancy and two weeks after birth, the newborn fetus has hypobiosis.When the morphological and functional readiness of all the main organs and life support systems is noted on extreme stimuli: decrease in motor activity, decrease in heart rate, decrease in the intensity of metabolic processes, low consumption of O 2 and CO 2 production , dominance of anaerobic glycolysis, acidosis, hypoglycemia, poikilothermia, immunological tolerance.

Hypobiosis is a protective mechanism that ensures the resistance of the organism of the fetus-newborn to adverse environmental influences.

A full-term newborn is a child born at a gestational age of 37-42 weeks. In a full-term newborn, due to the prevailing development of the brain, the head makes up 1/4 of the body. Of particular importance is the determination of head circumference at birth (and in dynamics) of body weight, as well as its shape. The variants of the normal form include the following: dolichocephalic - elongated in the anterior-posterior direction, brachiocephalic - in the transverse direction, and the tower skull. The bones of the skull are malleable, they can overlap each other along the sagittal and coronal sutures. Features are reflected in the maturity table.

A premature newborn is a baby born before 37 weeks of gestation. Live births at 22 to 28 weeks gestation and surviving the first 168 hours of life. Normal developmental parameters in terms of 28-37 weeks include children with a body weight of 1000.0 to 2500.0 g, a length of 38-47 cm, a head circumference of 26-34 cm and a chest of 24-33 cm. According to statistical data different countries Premature born from 6 to 13% of children.

Body weight cannot be the main criterion for prematurity. There is the concept of "low birth weight" or "low weight" - these are children weighing less than 2500.0 g at birth who were born at term.

Postterm newborns include children born after 294 days or 42 weeks of gestation. The frequency of birth of such children is from 8 to 12%. In children, clinical signs of trophic disorders are observed: a decrease in skin turgor, thinning of the subcutaneous fat layer, desquamation, dryness and peeling of the skin, lack of lubrication, dense skull bones, often with closed sutures.

The study of the shape and size of the fetal head is of particular importance in obstetrics. In the vast majority of births (96%), the head first passes through the birth canal, making a series of successive movements (turns).

The head, due to its density and size, experiences the greatest difficulties in passing through the birth canal. After the birth of the head, the birth canal is usually sufficiently prepared to advance the trunk and limbs of the fetus. The study of the head is important for the diagnosis and prognosis of childbirth: the location of the sutures and fontanelles is used to judge the mechanism of childbirth and their course.

Mature fruit head: 1) The facial bones are firmly connected. 2) The bones of the cranial part are connected by sutures. 3) Fontanelles. 4) When passing through the birth canal, the sutures and fontanelles allow the bones of the skull to go behind each other. The bones of the fetal skull bend easily. The skull of the fetus consists of two frontal, two parietal, two temporal and one occipital, main and ethmoid bones. In obstetrics, the following sutures are of particular importance: arrow seam(sutura sagitalis) passes between the parietal bones. In front, the seam passes into a large fontanelle, in the back - into a small one. frontal suture(sutura frontalis) is located between the frontal bones; has the same direction as the swept seam. Coronal suture(sutura caronalis) connects the frontal bones with the parietal, runs perpendicular to the sagittal and frontal sutures. Lambdoid seam(sutura lambdoidea) connects the occipital bone with the parietal.

The large (anterior) fontanel (fonticulus magnus s. anterior) is located at the junction of the sagittal, frontal and coronal sutures, has a diamond shape. Four sutures extend from the large fontanelle: frontal sutures anteriorly, swept posteriorly, corresponding sections of the coronal suture to the right and left.

The small (posterior) fontanel (fonticulus parvus, s posterior) is a small depression in which the sagittal and lambdoid sutures meet. The small fontanel has a triangular shape; three sutures depart from the small fontanel: anteriorly swept, to the right and left the corresponding sections of the lambdoid suture.

There are four secondary fontanelles: two each on the right and left sides of the skull. Pterygoid fontanel (pterion) is located at the junction of the parietal, main, frontal and temporal bones. The stellate fontanel (asterion) is located at the junction of the parietal, temporal and occipital bones.

Dimensions heads mature fruit are as follows:

The direct size (diameter fronto-occipitalis) - from the glabella (glabella) to the occiput - is 12 cm. The circumference of the head in direct size (circumferentia fronto-occipitalis) - 34 cm.

Large oblique size (diameter mento-occipitalis) - from the chin to the occiput - is 13-13.5 cm. The head circumference for this size (circumferentia mento-occipitalis) is 38-42 cm.

Small oblique size (diameter suboccipito-bregmaticus) - from the suboccipital fossa to the first corner of the large fontanel - is 9.5 cm. The head circumference corresponding to this size (circumferentia suboccipito-bregmatica) is 32 cm.

The average oblique size (diameter suboccipitio-frontalis) - from the suboccipital fossa to the border of the scalp of the forehead - is 10 cm. The head circumference for this size (circumferentia suboccipito-frontalis) is 33 cm.

The sheer or vertical size (diameter verticalis, s. trashelo-bregmaticus) - from the top of the crown (crown) to the sublingual region - is 9.5-10 cm. The head circumference corresponding to this size (cipcumferentia trashelo-bregmatica) is 32 cm.

Large transverse size (diameter biparietalis) - the largest distance between the parietal tubercles is 9.25-9.5 cm.

Small transverse size (diameter bitemporalis) - the distance between the most distant points of the coronal suture - 8 cm.

Dimensions torso the following:

The size of the shoulders - the diameter of the shoulder girdle (diameter biacromialis) - is 12 cm. The circumference of the shoulder girdle is 35 cm.

The transverse size of the buttocks (diameter bisiliacalis) is 9-9.5 cm. The circumference is 28 cm.

35. The first toilet of a newborn. Processing of the umbilical cord. Prevention of ophthalmoblenorrhea.

Immediately after the birth of the head, it is necessary to suck out from the oral cavity and nasopharynx using a catheter connected to an electric vacuum device, masses consisting of amniotic fluid, mucus and blood. The child is taken to a warm tray covered with two sterile diapers, located at the mother's feet and carried out: 1) repeated aspiration from the oral cavity and nasopharynx; 2) prevention of blenorea; 3) primary ligation of the umbilical cord; 4) show the child to the mother and lay it on the stomach; 5) evaluate the state on the Apgar scale in the first minute.

Secondary treatment of the umbilical cord and secondary prevention of blenorea is carried out in a specially designated place for newborns on a heated changing table and, only if the midwife is dressed in a sterile gown and her hands are prepared in compliance with the rules of asepsis and antisepsis. The staple is not applied to the umbilical cord residue, but is replaced with a ligature under the condition of: thick and juicy umbilical cord, Rh-negative mother's blood, low-weight newborns and children in serious condition. The primary treatment of the skin, weighing, measuring the length, head circumference, chest circumference and swaddling are carried out. Without fail, before the mother and child are transferred to the postpartum department, the baby is applied to the mother's breast.

36. Honey and non-medical indications for abortion late dates. Late term abortion methods.

37. Fetal hypoxia. The reasons. Classification. Diagnosis and treatment.

Fetal hypoxia (HP) is a pathological condition that develops under the influence of oxygen deficiency during pregnancy and childbirth.

Etiopathogenesis: 1) fetoplacental insufficiency in obstetric and extragenital pathology 2) Violations of the structure of the placenta, 3) medications Þ chronic fetal hypnoxia, accompanied by ¯ tension of O2 in the blood, CO2, decompensated acidosis, impaired EBV, a decrease in the content of corticosteroids Þ on the functions of the central nervous system, cardiovascular system, regulation of homeostasis, vascular permeability, a decrease in the immunological reactivity of the fetal body. Hypoxic states of the fetus are associated with changes in the complex mother-placenta-fetus system.

Distinguish acute and chronic GP. Symptoms of acute fetal hypoxia often occur during childbirth. Chronic fetal hypoxia (more than 7-10 days) is a consequence of a long-term obstetric or extragenital pathology, leading to a retardation of the fetus in development.

Clinic: 1) violation of heart rate (first tachy-, then bradycardia), 2) deterioration in the sonority of heart tones Þ 3) increasing deafness of tones); 4) appearance of arrhythmia Þ 5) decreased fetal movement 6) passing meconium, 7) changes in the indicators of CBS, amniotic fluid and fetal blood.

Diagnostics: 1) registration of his cardiac activity. 2) Fetal CTG. 3) Functional load test (diagnosis of chronic fetal hypoxia). 4) oxytocin test. 5) Tests with holding the breath on inspiration and on exhalation. 6) The cold test gives a decrease in heart rate up to 10 beats. in min. During hypoxia, there are no rhythm changes. 7) Ultrasound (fetometry, placentography, "Biophysical profile"), 8) doppler flowmetry, 9) amniocentesis (pH of amniotic fluid, delta OD450, hormone levels, phospholipids), 10) cordocentesis (blood counts), 11) cardiomonitoring with computer evaluation of the obtained data, blood pH from the skin of the fetal head (during childbirth).

Treatment: a) treatment of the underlying disease of the mother, b) regulation of uterine tone, in) FPI correction

Compliance with bed rest (preferably on the left side to exclude inferior vena cava syndrome - the so-called "crocodile posture"). 1- Oxygen therapy. 2- In / in glucose (500 ml - 10% solution) + 10 units of insulin + cocarboxylase 100 mg + Vit C (10 ml - 5%). 3- In / improved uteroplacental circulation: eufillin, sigetin, ATP or chimes. Reopoliklyukin 200 ml intravenous drip. 4- Use of tocolytics: MgSO4 or Alupent.

Scheme treatment of acute hypoxia fetus: Position on the left side, O2, IV 100 ml of 10% glucose solution + 4 units of insulin + 50 mg of cocarboxylase and 5 ml of 5% Vit C, 10 ml of 2.4% solution of eufillin IV slowly + 2 ml 1 % sigetin + ATP (2 ml - 1%), intravenous drip of NaHCO3 (60-80 ml - 5%). In / in 10 ml of 10% Ca gluconate solution. If the presenting part is available, atropine sulfate is administered subcutaneously to the fetus (0.1 ml -0.1%). In the absence of the effect of the treatment of acute and chronic GP, urgent delivery is indicated.

8. Signs of fetal maturity, dimensions of the head and body of a mature fetus

The length (height) of a mature full-term newborn ranges from 46 to 52 cm or more, averaging 50 cm. The average body weight of a mature full-term newborn is 3400–3500 g. A mature full-term newborn has a well-developed subcutaneous fat layer; skin pink, elastic; the vellus cover is not pronounced, the length of the hair on the head reaches 2 cm; ear and nasal cartilages are elastic; nails are dense, protruding beyond the edges of the fingers. The umbilical ring is located in the middle of the distance between the womb and the xiphoid process. In boys, the testicles are descended into the scrotum. In girls, the small labia are covered with large ones. The cry of a child is loud. Muscle tone and movements of sufficient strength. The sucking reflex is well expressed.

The main feature of the cranial part of the head is that its bones are connected by fibrous membranes - sutures. In the area of the suture connection there are fontanelles - wide areas of connective tissue. A large head can change its shape and volume, as the sutures and fontanelles allow the bones of the skull to overlap each other. Due to this plasticity, the head adapts to the mother's birth canal. The most important sutures connecting the bones of the fetal skull are the following: the sagittal suture, passing between the two parietal bones; frontal suture - between two frontal bones; coronal suture - between the frontal and parietal bone; lambdoid (occipital) suture - between the occipital and parietal bones. Among the fontanelles on the head of the fetus, large and small fontanelles are of practical importance. The large (anterior) fontanel is diamond-shaped and is located at the junction of the sagittal, frontal, and coronal sutures. The small (posterior) fontanelle has a triangular shape and is a small depression in which the sagittal and lambdoid sutures converge.

Head full-term mature fetus has the following dimensions:

1) direct size (from the bridge of the nose to the occiput) - 12 cm, head circumference in direct size - 34 cm;

2) large oblique size (from the chin to the occiput) - 13–13.5 cm; head circumference - 38–42 cm;

3) small oblique size (from the suboccipital fossa to the anterior angle of the large fontanel) - 9.5 cm, head circumference - 32 cm;

4) average oblique size (from the suboccipital fossa to the border of the scalp of the forehead) - 10 cm; head circumference - 33 cm;

5) sheer, or vertical, size (from the top of the crown to the sublingual region) - 9.5-10 cm, head circumference - 32 cm;

6) large transverse dimension (the largest distance between the parietal tubercles) - 9.5 cm;

7) small transverse dimension (distance between the most distant points of the coronal suture) - 8 cm.

Dimensions torso fruit are as follows:

1) the size of the shoulders (diameter of the shoulder girdle) - 12 cm, the circumference of the shoulder girdle - 35 cm;

2) the transverse size of the buttocks is 9 cm, the circumference is 28 cm.

The head of a full-term mature fetus has the following dimensions:

1) direct size (from the bridge of the nose to the occiput) - 12 cm, head circumference in direct size - 34 cm;

2) large oblique size (from the chin to the occiput) - 13–13.5 cm; head circumference - 38–42 cm;

3) small oblique size (from the suboccipital fossa to the anterior angle of the large fontanel) - 9.5 cm, head circumference - 32 cm;

4) average oblique size (from the suboccipital fossa to the border of the scalp of the forehead) - 10 cm; head circumference - 33 cm;

5) sheer, or vertical, size (from the top of the crown to the sublingual region) - 9.5-10 cm, head circumference - 32 cm;

6) large transverse dimension (the largest distance between the parietal tubercles) - 9.5 cm;

7) small transverse dimension (distance between the most distant points of the coronal suture) - 8 cm.

The dimensions of the body of the fetus are as follows:

1) the size of the shoulders (diameter of the shoulder girdle) - 12 cm, the circumference of the shoulder girdle - 35 cm;

2) the transverse size of the buttocks is 9 cm, the circumference is 28 cm.

Head term mature fetus has the following dimensions
Dimensions torso fetus the following: 1) the size shoulders (diameter of the shoulder girdle) - 12 cm, circumference of the shoulder girdle - 35 cm

signs maturity fetus, dimensions heads and torso mature fetus. Length (height) mature full-term newborn ranges from 46 to 52 cm or more, amounting to c. Loading.

signs maturity fetus, dimensions heads and torso mature fetus. Length (height) mature full-term newborn ranges from 46 to 52 cm or more, amounting to an average ... more ».

signs maturity fetus, dimensions heads and torso mature fetus. Length (height) mature full-term newborn ranges from 46 to 52 cm or more, amounting to c. Diagnosis of pregnancy.

On the onset labor activity it may be found that dimensions pelvis and heads fetus do not match each other.
With breech presentation signs hydrocephalus is detected only after birth torso.

Delivery through the natural birth canal is possible with a mild form of premature detachment of the placenta, in the case of head presentation fetus, at mature cervix, compliance heads fetus mother's pelvis and subject to normal birth ...

Childbirth with extensor presentation heads fetus.
Internal rotation of the shoulders and the associated external rotation torso ends at the exit from the small pelvis and is characterized by the fact that the shoulders are set in a straight line size.

When flexed head fetus belongs to its smallest size.
When unbending, the parietal region, forehead, face and chin are sequentially born from the genital tract. Outer turn heads and inner turn torso.

Anterior presentation fetus(first degree of extension). In this case, a large fontanel is a wire point, head direct size passes through the plane of the pelvis.

Birth heads. When trying, the genital gap is stretched head fetus.
At the same time, the shoulders stand in a straight line. size pelvis (internal rotation of the shoulders). Birth torso.

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The fetus as an object of childbirth is considered mainly taking into account the size of the head. The head is the most voluminous and dense part, experiencing the greatest difficulties in moving along the birth canal. It is a benchmark by which the dynamics and effectiveness of labor activity are assessed.

A full-term fetus has an average weight of 3000 - 3500 g, a length of 50 cm. The brain part of the skull is formed by 7 bones: two frontal, two temporal, two parietal and one occipital. Separate bones of the skull are connected by sutures and fontanelles. The fetal head has elasticity and is able to shrink in one direction and increase in the other.

Seams and fontanelles have diagnostic value in childbirth: frontal suture (sutura frontalis), separating both frontal bones in the sagittal direction; swept (s.sagitahs) separates the parietal bones from each other; coronary (s.coronaria) - the frontal bone from the parietal; lambdoid (s.lambdoidea) - parietal bones from the occipital; temporal fs.temporalis) - temporal bones from the parietal.

A large fontanel, or front (fonticulus magnus), has the shape of a rhombus. In the center between the four bones (two frontal and two parietal) four sutures converge to it - the frontal, sagittal and two branches of the coronary)

The small fontanel (f.parvus), or posterior, is a small depression in which three seams converge - swept and both legs of the lambdoid.

To understand the biomechanism of childbirth, it is important to know the following head sizes:

large oblique (diameter mento-occipitalis) - from the chin to the most distant point on the back of the head - 13.5 cm, with a corresponding circumference of 40 cm along it;

small oblique (d.suboccipito-bregmatika) - from the suboccipital fossa to the anterior corner of the large fontanel -9.5 cm, with a circumference of 32 cm;

medium oblique (d. suboccipito-frontalis) - from the suboccipital fossa to the border of the scalp of the forehead - 9.5 - 10.5 cm, with a circumference of 33 cm;

straight (d.fronto-occipitalis) - from the bridge of the nose to the occiput - 12 cm, with a circumference of 34 cm; sheer, or vertical (d.tracheo-bregmatica), - from the top of the crown to the hyoid bone - 9.5 cm, with a circumference of 33 cm; large transverse (d.biparietalis) - the largest distance between the parietal tubercles - 9.25 cm; small transverse (d.bitemporalis) - the distance between the most distant points of the coronal suture is 8 cm.

Body dimensions: shoulder girdle - circumference at the level of the shoulders - 35 cm, shoulder size - the diameter of the shoulder girdle (distantia biacromialis) - 22 cm. The transverse size of the buttocks (distantia biiliacalis) - 9.0 - 9.5 cm the level of the trochanters of the femur is -27-28 cm. These dimensions are also important in the process of childbirth.

The position of the fetus (situs) is the ratio of the longitudinal axis of the fetus to the length of the uterus. There are longitudinal, transverse and oblique position of the fetus.

The position of the fetus (positio) is the ratio of its back to the right or left side of the mother's body (the wall of the uterus). If the back is turned to the left half of the body of the uterus, then this is the first position, to the right - the second position.

Type of position (visus) - the ratio of the back of the fetus to the anterior and posterior walls of the uterus. If the back is turned forward - front view, backward - rear view.

Presentation of the fetus (praesentatio) - the ratio of a large part of the fetus to the entrance to the pelvis. Distinguish between head and breech presentation or presentation of the shoulder in the transverse position.

The articulation of the fetus (habitus) is the mutual position of the various parts of the fetus in relation to its body and to each other.

Typical articulation: the head is bent; the chin is in contact with the chest; the back is bent; the arms are crossed, bent and placed on the chest; the legs are bent at the hip and knee joints; the umbilical cord is located on the tummy between the limbs. If the head is unbent, then its extensor presentation (frontal, facial or anteroparietal) takes place.

Insertion of the head (inclinatio) - the ratio of the swept seam to the entrance to the pelvis, i.e. to the cape and symphysis.

Scheme of positions and presentations:

I. Longitudinal positions (99.5%).

Head presentation (94%), flexion (93%) and extensor (1%) types.

Breech presentation (5.5%), flexion (4%), extensor (full and incomplete foot) (1.5%) types.

II. Transverse and oblique positions (0.5%).

Establishment of full-term. A normal pregnancy in a woman lasts an average of 10 lunar months (280 days) and ends with a physiological birth with a full-term fetus. Hence, a full-term baby is considered to be born after 38-40 weeks of pregnancy.

Establishing the maturity of the fetus and duration of intrauterine life. The maturity of the fetus is understood as the degree of its physical development, which ensures the readiness of organs and systems for extrauterine existence. Maturity is characterized by a set of features, which include: body length and weight, head size, condition of the skin, hair, nails, external genitalia, umbilical cord, placenta, ossification nuclei.

Maturity is determined not by any one sign, but by a complex, a combination of them, since the severity of these signs, even in a mature fetus, can be different.

A full-term fetus is usually mature.

If it is determined that the infant is premature and immature, then it is necessary to establish its intrauterine age. To do this, use a simple formula: if the length of the fetus is more than 25 cm, it is divided by 5, if the length of the fetus is less than 25 cm, then the square root is taken, the result obtained during the actions and will show the intrauterine age of the fetus in lunar months (obstetric).

It is possible to estimate the intrauterine age of the fetus by the length of the umbilical cord and the weight of the placenta

Gestational age, months Umbilical cord length, cm Placenta weight, g