Not in any section embryology there was not as much speculation as there was in the matter of determining gender. Since time immemorial, numerous theories have been put forward seeking to explain why one embryo becomes a male and another becomes a female. However, all these theories have been discredited. In this regard, researchers have become especially careful when discussing any new theory in this area.
But at present, so many interesting things have appeared in connection with the chromosomal theory of sex determination that it is necessary to get acquainted with it.

When considering divisions maturation It has already been indicated that the chromosomes present in the cells of a given species can be arranged in pairs, the members of which are very similar to each other. However, in a man, one pair of chromosomes is an exception, since its chromosomes are not the same. The members of this pair are called the X and Y chromosomes. Although our information about them is still fragmentary and insufficient, there is a lot of data showing that from X-Y pairs chromosomes determine sex, which is why they are usually called “sex chromosomes.”

In the cells of a female individual in a similar pair chromosomes Instead of the large X and small Y chromosomes characteristic of males, there are only two large X chromosomes. In this case, we can detail our previous statement that human cells contain 24 pairs of chromosomes, forming a species number of 48. We can now say that in a male somatic cell there are 23 pairs of identical chromosomes and one pair of different chromosomes, made up of X- and Y chromosomes. The number of chromosomes in a woman’s somatic cell is also equal to 23 pairs of identical chromosomes and one pair consisting of X chromosomes, one of which in its location corresponds to the small Y chromosome in a man.

Careful Study maturation gametes made it possible to find out how this sexual difference in the chromosome set is created and maintained. During synapsis, observed during maturation divisions, two sex chromosomes, as in any other chromosome pair, are connected to each other. During the reduction division of spermatocytes, the X chromosomes move into one cell, and the Y chromosomes into another.

With equational division all daughter cells will have the same set of chromosomes. Consequently, after two divisions of maturation, from each first-order spermatocyte, two spermatozoa are formed, each having 23 somatic chromosomes and an X chromosome, as well as two spermatozoa, each having 23 somatic chromosomes and a Y chromosome. Since all cells of a female individual contain a combination of X-X chromosomes, during the reduction division that occurs during the maturation of the egg, one of the X chromosomes must pass into the polar body, and the other into the maturing egg. The set of chromosomes in eggs always consists of 23 somatic chromosomes and one X chromosome.

When egg, ready for fertilization, will be surrounded by sperm, half of which have one set of chromosomes, and the other half - another, it is clear that sperm of either type have an equal chance of penetrating the egg.

If it penetrates sperm containing an X chromosome, then as a result of fertilization, an X-X combination is formed in the zygote, characteristic of a female individual. If a sperm carrying a Y chromosome penetrates the egg, an X-Y combination is formed, characteristic of a male individual. If, for the sake of simplicity of the image, we use the sex cells of an animal whose species number of chromosomes is only eight, then the main points of the chromosomal theory of sex determination can be schematically summarized.

The reliability of this theories supported by more evidence than any other theory. However, it must be recognized that we know practically nothing about the mechanism of action of various chromosome sets that determine the sex of the offspring. It is indicated that the set of chromosomes established during fertilization provides only the initial impetus for sexual differentiation in one direction or another, and that the actions of certain internal environmental factors can have a great influence on the final differentiation of sex. For people trying to find a way to control the sex of their offspring, only one answer can be given so far: as far as we know, determining the sex of a child is a matter of chance and is still beyond our capabilities. Promising to influence the outcome means keeping company with the healers of primitive tribes or branding yourself as a charlatan.

We still have to deal with the myth that the human embryo initially develops according to women's path, and only then in future boys, under the influence of androgens, male genital organs are formed from the female genital organs. This is wrong.

Genetic determination of sex occurs at fertilization. The Y chromosome is the determinant of the genetically male sex (the zygote contains 22 pairs of autosomes + XY sex chromosomes, i.e. 46XY). The karyotype of the genetically female zygote is 46XX.

Until approximately the 6-7th week of the embryo's intrauterine life, its gonads develop identically in both men and women. This is the so-called indifferent stage embryo development, when the reproductive system of both sexes develops according to the same genetic program.
During the formation of the gonadal sex, the fetus develops male ( Wolff) and female ( Müller) ducts. Initially, the development of these ducts begins unipotentially, that is, regardless of the future sex, and only one of them can develop into the reproductive tract associated with the specific genetic sex of the fetus. In particular, the Wolffian duct turns into the structures of the male reproductive tract, and the Müllerian duct - the female. The simultaneous presence of the Wolffian and Müllerian ducts at this stage is a legacy from our distant hermaphrodite ancestors who lived hundreds of millions of years ago.

Primary germ cells are formed in the wall of the yolk sac and at the 5th week of embryogenesis they begin to migrate into the gonadal ridges - rudiments indifferent gonads IN indifferent period During the development of primary gonads, their stromal tissue contains two types of cells. One cell type at the gonadal stage of sex differentiation develops into granulosa cells in the ovaries or Sertoli cells of the seminiferous tubules in the testes. The second type of cells at the gonad stage differentiate into cells of the transparent membrane (theca pellucida) in the ovaries or Leydig cells in the testes.

In the embryo male at the 6-7th week of embryonic life after migration of primary germ cells into the primary gonads in the presence of a Y chromosome containing SRY gene, differentiation occurs Sertoli cells. During the process of differentiation, Sertoli cells are located around the primary germ cells, resulting in the development of testicular tubes in the primary gonads. Differentiation of mesenchymal (stromal) cells of the gonads into interstitial Leydig cells, which will subsequently secrete the male sex hormone testosterone, begins at the 8-9th week and ends at the 10th week of fetal development.
In the female embryo, differentiation of the primary gonads into ovaries (determined FOXL2 genome) begins from the 9th week, when the X chromosomes are activated. If the FOXL2 gene malfunctions, the primary gonads will develop into... testicles!

Development internal male genital organs in the fetus occurs under the influence of testosterone. The secretion of testosterone by Leydig cells in a male fetus begins around the 8-9th week of development, under the influence of placental chorionic gonadotropin, the secretion of which is stimulated by growth hormone. Influenced testosterone Wolffian ducts are transformed in their development into epididymis, vas deferens and seminal vesicles.
The Sertoli cells of the fetal testes secrete müllerian inhibitory factor(synonym - anti-mullerian hormone), calling regression Müllerian ducts in a male fetus.

In a developing fetus according to the female type, granulosa cells and zona pellucida cells do not secrete anti-Mullerian hormone and testosterone. In the absence of anti-Müllerian hormone, the Müllerian ducts develop into internal female reproductive organs (fallopian tubes, uterus, upper vagina), and at the same time regression Wolffian ducts due to the lack of testosterone secretion in the fetus.

Differentiation of the external genitalia occurs from the urogenital sinus, genital tubercle, genital folds and genital ridges. The development of the external genitalia depends on sex hormones.
In a developing fetus male type, influenced testosterone The urogenital sinus gives rise to the prostate and bulbourethral glands.
5-alpha reductase catalyzes the conversion of testosterone to dihydrotestosterone. At approximately the 12th week of intrauterine development, the genital tubercle is influenced dihydrotestosterone differentiates into the penis, the genital folds form the distal part of the urethra, and the genital ridges develop into the scrotum.
In a developing fetus according to the female type, in the absence of androgens, at approximately the 14th week of intrauterine development, the urogenital sinus develops into the lower part of the vagina, the genital tubercle into the clitoris, and the genital folds and genital ridges differentiate into the labia minora and majora, respectively. Female sex hormones promote the differentiation of extragonadal organs of the female reproductive system.

As we can see, a fetus with an XY karyotype cannot be considered a female fetus at any stage.

Pregnancy is a physiological process in which a new human organism develops in a woman’s uterus, resulting from fertilization.

Pregnancy lasts on average for women 280 days(40 weeks, which corresponds to 9 calendar months or 10 lunar months). Pregnancy is also usually divided into 3 trimesters of 3 calendar months each.

Signs of early pregnancy

IN early dates The diagnosis of pregnancy is established on the basis of doubtful and probable signs.

Questionable signs of pregnancy- various kinds of subjective sensations, as well as objectively determined changes in the body, outside the internal genital organs: taste whims, changes in olfactory sensations, easy fatigue, drowsiness, pigmentation of the skin on the face, along the white line of the abdomen, nipples and areola.

Possible signs of pregnancy- objective signs from the genital organs, mammary glands and when staging biological reactions to pregnancy. These include: cessation of menstruation in women of childbearing age, enlargement of the mammary glands and the appearance of colostrum when squeezed out of the nipples, cyanosis of the mucous membrane of the vagina and cervix, changes in the shape and consistency of the uterus, and an increase in its size.

You can first verify the presence of pregnancy at home using a rapid test for the content of the hormone human chorionic gonadotropin in a woman’s urine (the test is carried out from the first day of the delay of the next menstruation).

It allows you to confirm the fact of pregnancy.

Changes in the body of a pregnant woman

Numerous and complex changes occur in a woman's body during pregnancy. These physiological changes create conditions for intrauterine development of the fetus, prepare the woman’s body for childbirth and breastfeeding newborn Menstruation stops, the mammary glands increase in volume, and the nipples darken.

Many pregnant women experience nausea and sometimes vomiting in the first trimester - these symptoms are commonly called. Weakness, drowsiness, heartburn, drooling, changes in taste, and frequent urination often occur. These disturbances in well-being are characteristic of a healthy and normal pregnancy.

Particularly large changes occur in the woman’s genital organs. Each time the uterus grows, the blood supply to the internal and external genital organs increases. The tissues swell and become elastic, which facilitates their better stretching during childbirth. In the mammary glands, the number and volume of glandular lobules increase, their blood supply increases, they become tense, from the nipples. There is a sharp increase in the amount of gonadotropic hormones, as well as estrogens and progesterone, produced first by the corpus luteum (a temporary gland formed at the site of the follicle from which the mature egg emerged) and then. Hormones secreted by the corpus luteum (progesterone and, to a lesser extent, estrogens) help create conditions for the proper development of pregnancy. The corpus luteum undergoes reverse development after the fourth month due to the development of the hormonal function of the placenta.

To manage pregnancy, it is necessary (3 - 4 weeks after the delay of menstruation), where the doctor examines and examines the external and internal genital organs, and, if necessary, prescribes additional examinations.

Genital organs during pregnancy

Uterus. During pregnancy, the size, shape, position, consistency and reactivity (excitability) of the uterus changes. The uterus gradually enlarges throughout pregnancy. Enlargement of the uterus occurs mainly due to hypertrophy of the muscle fibers of the uterus; At the same time, muscle fibers multiply and the newly formed muscle elements of the reticular-fibrous and argyrophilic “framework” of the uterus grow.

The uterus is not only a fruit repository that protects the fetus from adverse external influences, but also a metabolic organ that provides the fetus with enzymes and complex compounds necessary for the plastic processes of a rapidly developing fetus.

Vagina During pregnancy, it lengthens, widens, and the folds of the mucous membrane become more pronounced. The external genitalia loosen during pregnancy.

Lifestyle of a pregnant woman, regime, nutrition and hygiene

The developing fetus receives all the necessary nutrients from the mother. The well-being of the fetus depends entirely on the health of the mother, her working conditions, rest, and the state of the nervous and endocrine systems.

Pregnant women are exempt from night shifts, heavy physical work, work associated with body vibration or adverse effects of chemicals on the body. substances. During pregnancy, sudden movements, heavy lifting and significant fatigue should be avoided. A pregnant woman needs to sleep at least 8 hours a day. A walk before bed is recommended.

A pregnant woman must be carefully protected from infectious diseases, which pose a particular danger to the body of the pregnant woman and the fetus.

During pregnancy, you need to be especially careful about keeping your skin clean. Clean skin helps eliminate metabolic products harmful to the body through sweat.

A pregnant woman should wash her external genitalia twice a day with warm water and soap. Douching during pregnancy should be prescribed with great caution.

During pregnancy, you should carefully monitor the condition of your oral cavity and carry out the necessary treatment.

The mammary glands must be washed daily with warm water and soap and dried with a towel. These methods prevent cracked nipples and mastitis. If so, then you should massage them.

Maternity clothes should be comfortable and loose: you should not wear tight belts, tight bras, etc. In the second half of pregnancy, it is recommended to wear a bandage that should support the abdomen, but not squeeze it.

A pregnant woman should wear low-heeled shoes.

Pregnancy is a physiological process in which a new organism develops in the uterus, resulting from fertilization. Pregnancy lasts on average 40 weeks (10 obstetric months).

In the intrauterine development of a child, two periods are distinguished:

1. Embryonic(up to 8 weeks of pregnancy inclusive). At this time, the embryo is called an embryo and acquires characteristic human features;
2. Fetal(from 9 weeks until birth). At this time, the embryo is called a fetus.

The growth of a child, the formation of its organs and systems occurs naturally during various periods of intrauterine development, which is subject to the genetic code embedded in the germ cells and fixed in the process of human evolution.

Embryo development in the first obstetric month (1-4 weeks)

First week (days 1-7)

Pregnancy begins from the moment fertilization- fusion of a mature male cell (sperm) and a female egg. This process usually occurs in the ampullary section of the fallopian tube. After a few hours, the fertilized egg begins to divide exponentially and descends through the fallopian tube into the uterine cavity (this journey takes up to five days).

As a result of division turns out to be a multicellular organism, which is similar to a blackberry (in Latin “morus”), which is why the embryo at this stage is called Morula. Approximately on the 7th day, the morula penetrates the uterine wall (implantation). The villi of the outer cells of the embryo connect with the blood vessels of the uterus, and subsequently the placenta is formed from them. Other outer morula cells give rise to the development of the umbilical cord and membranes. Over time, various tissues and organs of the fetus will develop from the internal cells.

Information At the time of implantation, a woman may have slight bleeding from the genital tract. Such discharge is physiological and does not require treatment.

Second week (8-14 days)

The outer morula cells grow tightly into the lining of the uterus. In the embryo the formation of the umbilical cord and placenta begins, and neural tube, from which the fetal nervous system subsequently develops.

Third week (15-21 days)

The third week of pregnancy is a difficult and important period. At that time important organs and systems begin to form fetus: the rudiments of the respiratory, digestive, circulatory, nervous and excretory systems appear. At the site where the fetal head will soon appear, a wide plate is formed, which will give rise to the brain. On day 21, the baby's heart begins to beat.

Fourth week (22-28 days)

this week laying of fetal organs continues. The rudiments of the intestines, liver, kidneys and lungs are already present. The heart begins to work more intensely and pumps more and more blood through the circulatory system.

From the beginning of the fourth week in the embryo body folds appear, and appears rudiment of the spine(chord).

Completed by day 25 neural tube formation.

By the end of the week (approximately 27-28 days) the muscular system and spine are formed, which divides the embryo into two symmetrical halves, both upper and lower limbs.

During this period it begins formation of pits on the head, which will later become the eyes of the fetus.

Development of the embryo in the second obstetric month (5-8 weeks)

Fifth week (29-35 days)

During this period the embryo weighs about 0.4 grams, length 1.5-2.5 mm.

The formation of the following organs and systems begins:

1. Digestive system: liver and pancreas;
2. Respiratory system: larynx, trachea, lungs;
3. Circulatory system;
4. Reproductive system: precursors of germ cells are formed;
5. Sense organs: eye and inner ear formation continues;
6. Nervous system: the formation of parts of the brain begins.

At that time a faint umbilical cord appears. The formation of limbs continues, the first rudiments of nails appear.

On the face the upper lip and nasal cavities are formed.

Sixth week (36-42 days)

Length embryo during this period is about 4-5 mm.

Starts in the sixth week formation of the placenta. At this stage, it is just beginning to function; blood circulation between it and the embryo has not yet been formed.

Ongoing formation of the brain and its parts. At the sixth week, when performing an encephalogram, it is already possible to record signals from the fetal brain.

Begins formation of facial muscles. The fetal eyes are already more pronounced and uncovered by eyelids that are just beginning to form.

During this period they begin upper limbs change: they lengthen and the rudiments of hands and fingers appear. The lower limbs still remain in their infancy.

Changes in important organs occur:

1. Heart. The division into chambers is completed: ventricles and atria;
2. Urinary system. Primary kidneys have formed, the development of the ureters begins;
3. Digestive system. The formation of sections of the gastrointestinal tract begins: the stomach, small and large intestines. The liver and pancreas had practically completed their development by this period;

Seventh week (43-49 days)

The seventh week is significant because The formation of the umbilical cord is completed and uteroplacental circulation is established. Now the breathing and nutrition of the fetus will be carried out due to blood circulation through the vessels of the umbilical cord and placenta.

The embryo is still bent in an arched manner; there is a small tail on the pelvic part of the body. The size of the head is at least half of the embryo. The length from the crown to the sacrum increases by the end of the week up to 13-15 mm.

Ongoing upper limb development. The fingers are visible quite clearly, but their separation from each other has not yet occurred. The child begins to perform spontaneous movements with his hands in response to stimuli.

Fine eyes are formed, already covered with eyelids, which protect them from drying out. The child can open his mouth.

The formation of the nasal fold and nose occurs, two paired elevations are formed on the sides of the head, from which they will begin to develop ears.

Intensive continues development of the brain and its parts.

Eighth week (50-56 days)

The body of the embryo begins to straighten, length from the crown to the coccyx is 15 mm at the beginning of the week and 20-21 mm on day 56.

Ongoing formation of important organs and systems: digestive system, heart, lungs, brain, urinary system, reproductive system (boys develop testicles). The hearing organs are developing.

By the end of the eighth week the child's face becomes familiar to the person: the eyes are well defined, covered with eyelids, the nose, the ears, the formation of the lips is ending.

Intensive growth of the head, upper and lower horses is noted In particular, ossification of the long bones of the arms and legs and the skull develops. The fingers are clearly visible; there is no skin membrane between them.

Additionally At eight weeks the embryonic period of development ends and the fetal period begins. From this time on, the embryo is called a fetus.

Fetal development in the third obstetric month (9-12 weeks)

Ninth week (57-63 days)

At the beginning of the ninth week coccygeal-parietal size fetus is about 22 mm, by the end of the week - 31 mm.

Happening improvement of blood vessels of the placenta, which improves uteroplacental blood flow.

The development of the musculoskeletal system continues. The process of ossification begins, the joints of the toes and hands are formed. The fetus begins to make active movements and can clench its fingers. The head is lowered, the chin is pressed tightly to the chest.

Changes occur in the cardiovascular system. The heart beats up to 150 times per minute and pumps blood through its blood vessels. The composition of blood is still very different from the blood of an adult: it consists only of red blood cells.

Ongoing further growth and development of the brain, cerebellar structures are formed.

The organs of the endocrine system are intensively developing, in particular, the adrenal glands, which produce important hormones.

Improves cartilage tissue: auricles, laryngeal cartilages, education is underway vocal cords.

Tenth week (64-70 days)

By the end of the tenth week fruit length from the coccyx to the crown is 35-40 mm.

Buttocks begin to develop, the previously existing tail disappears. The fetus is in the uterus in a fairly free position in a semi-bent state.

Nervous system development continues. Now the fetus performs not only chaotic movements, but also reflex ones in response to a stimulus. When accidentally touching the walls of the uterus, the child makes movements in response: turns his head, bends or straightens his arms and legs, and pushes to the side. The size of the fetus is still very small, and the woman cannot yet feel these movements.

The sucking reflex is formed, the child begins reflex movements with his lips.

The development of the diaphragm is completed, which will take an active part in breathing.

Eleventh week (71-77 days)

By the end of this week coccygeal-parietal size the fetus increases to 4-5 cm.

The fetal body remains disproportionate: small body, large head, long arms and short legs, bent at all joints and pressed to the stomach.

The placenta has already reached sufficient development and copes with its functions: ensures the supply of oxygen and nutrients to the fetus and removes carbon dioxide and metabolic products.

Further formation of the fetal eyes occurs: At this time, the iris develops, which will later determine the color of the eyes. The eyes are well developed, half-closed or wide open.

Twelfth week (78-84 days)

Coccygeal-parietal size fetus is 50-60 mm.

Goes clearly development of the genital organs according to the female or male type.

Happening further improvement of the digestive system. The intestines are elongated and arranged in loops, like those of an adult. Its periodic contractions - peristalsis - begin. The fetus begins to make swallowing movements, swallowing amniotic fluid.

The development and improvement of the fetal nervous system continues. The brain is small in size, but exactly replicates all the structures of the adult brain. The cerebral hemispheres and other sections are well developed. Reflex movements are improved: the fetus can clench and unclench its fingers into a fist, grabs the thumb and actively sucks it.

In fetal blood Not only red blood cells are already present, but the production of white blood cells - leukocytes - also begins.

At this time the child single respiratory movements begin to be recorded. Before birth, the fetus cannot breathe, its lungs do not function, but it makes rhythmic movements of the chest, imitating breathing.

By the end of the week the fetus eyebrows and eyelashes appear, the neck is clearly visible.

Fetal development in the fourth obstetric month (13-16 weeks)

Week 13 (85-91 days)

Coccygeal-parietal size by the end of the week is 70-75 mm. The proportions of the body begin to change: the upper and lower limbs and torso lengthen, the size of the head is no longer so large in relation to the body.

Improvement of the digestive and nervous systems continues. The embryos of baby teeth begin to appear under the upper and lower jaws.

The face is fully formed, the ears, nose and eyes are clearly visible (the eyelids are completely closed).

Week 14 (92-98 days)

Coccygeal-parietal size by the end of the fourteenth week it increases up to 8-9 cm. Body proportions continue to change to more familiar ones. The face has a well-defined forehead, nose, cheeks and chin. The first hair appears on the head (very thin and colorless). The surface of the body is covered with vellus hairs, which retain skin lubrication and thereby perform protective functions.

The musculoskeletal system of the fetus is improved. Bones become stronger. Motor activity increases: the fetus can turn over, bend, and make swimming movements.

Development of the kidneys, bladder and ureters is complete. The kidneys begin to secrete urine, which mixes with the amniotic fluid.

: pancreatic cells begin to work, producing insulin, and pituitary cells.

Changes in the genital organs appear. In boys, the prostate gland forms; in girls, the ovaries migrate into the pelvic cavity. At the fourteenth week, with a good sensitive ultrasound machine, it is already possible to determine the sex of the child.

Fifteenth week (99-105 days)

Coccygeal-parietal size of the fetus is about 10 cm, fruit weight – 70-75 grams. The head still remains quite large, but the growth of the arms, legs and torso begins to outstrip it.

The circulatory system is improved. In the fourth month, a child’s blood type and Rh factor can already be determined. Blood vessels (veins, arteries, capillaries) grow in length and their walls become stronger.

The production of original feces (meconium) begins. This is due to the ingestion of amniotic fluid, which enters the stomach, then into the intestines and fills it.

Fully formed fingers and toes, an individual design appears on them.

Sixteenth week (106-112 days)

The weight of the fetus increases to 100 grams, the coccygeal-parietal size - up to 12 cm.

By the end of the sixteenth week, the fetus is already fully formed, he has all the organs and systems. The kidneys are actively working, a small amount of urine is released into the amniotic fluid every hour.

The skin of the fetus is very thin, subcutaneous fatty tissue is practically absent, so blood vessels are visible through the skin. The skin appears bright red, covered with vellus hairs and grease. Well defined eyebrows and eyelashes. Nails are formed, but they only cover the edge of the nail phalanx.

Facial muscles are formed, and the fetus begins to “grimace”: frowning of the eyebrows and a semblance of a smile are observed.

Fetal development in the fifth obstetric month (17-20 weeks)

Seventeenth week (days 113-119)

The weight of the fetus is 120-150 grams, the coccygeal-parietal size is 14-15 cm.

The skin remains very thin, but subcutaneous fatty tissue begins to develop under it. The development of baby teeth continues, which are covered with dentin. The embryos of permanent teeth begin to form under them.

There is a reaction to sound stimuli. From this week we can say for sure that the child began to hear. When strong sharp sounds appear, the fetus begins to actively move.

Fetal position changes. The head is raised and is in an almost vertical position. The arms are bent at the elbow joints, the fingers are clenched into a fist almost all the time. Periodically, the child begins to suck his thumb.

The heartbeat becomes clear. From now on, the doctor can listen to him using a stethoscope.

Eighteenth week (120-126 days)

The child's weight is about 200 grams, length - up to 20 cm.

The formation of sleep and wakefulness begins. Most of the time the fetus sleeps, movements stop during this time.

At this time, the woman may already begin to feel the baby moving, especially with repeated pregnancies. The first movements are felt as gentle jolts. A woman may feel more active movements when she is nervous or stressed, which affects her emotional state child. At this stage, the norm is about ten episodes of fetal movement per day.

Nineteenth week (127-133 days)

The child’s weight increases to 250-300 grams, body length – to 22-23 cm. The proportions of the body change: the head lags behind the body in growth, the arms and legs begin to lengthen.

Movements become more frequent and noticeable. They can be felt not only by the woman herself, but also by other people by placing their hand on their stomach. Primigravidas at this time can only begin to feel movements.

The endocrine system is improved: the pancreas, pituitary gland, adrenal glands, gonads, thyroid and parathyroid glands are actively functioning.

Blood composition has changed: In addition to erythrocytes and leukocytes, the blood contains monocytes and lymphocytes. The spleen begins to take part in hematopoiesis.

Twentieth week (134-140 days)

Body length increases to 23-25 ​​cm, weight – up to 340 grams.

The fetal skin is still thin, covered with protective lubricant and vellus hairs, which can persist until childbirth. Subcutaneous fatty tissue develops intensively.

Well formed eyes, at twenty weeks the blink reflex begins to appear.

Improved movement coordination: The child confidently brings his finger to his mouth and begins to suck it. Facial expressions are pronounced: the fetus may close its eyes, smile, or frown.

This week all women are already feeling movements., regardless of the number of pregnancies. Movement activity varies throughout the day. When stimuli appear (loud sounds, stuffy rooms), the child begins to move very violently and actively.

Fetal development in the sixth obstetric month (21-24 weeks)

Twenty-first week (days 141-147)

Body weight grows to 380 grams, fetal length – up to 27 cm.

The layer of subcutaneous tissue increases. The skin of the fetus is wrinkled, with many folds.

Fetal movements become more active and tangible. The fetus moves freely in the uterine cavity: it lies head down or buttocks, across the uterus. Can pull on the umbilical cord, push off the walls of the uterus with hands and feet.

Changes in sleep and wakefulness patterns. Now the fetus spends less time sleeping (16-20 hours).

Twenty-second week (148-154 days)

At week 22, the size of the fetus increases to 28 cm, weight - up to 450-500 grams. The size of the head becomes proportional to the body and limbs. The legs are bent almost all the time.

The fetal spine is fully formed: It has all the vertebrae, ligaments and joints. The process of strengthening bones continues.

Improves the fetal nervous system: the brain already contains everything nerve cells(neurons) and has a mass of about 100 grams. The child begins to take an interest in his body: he feels his face, arms, legs, tilts his head, brings his fingers to his mouth.

Heart size increases significantly, the functionality of the cardiovascular system is improved.

Twenty-third week (155-161 days)

The length of the fetal body is 28-30 cm, weight is about 500 grams. Pigment begins to be synthesized in the skin, resulting in the skin acquiring a bright red color. The subcutaneous fatty tissue is still quite thin, as a result the child looks very thin and wrinkled. The lubricant covers the entire skin and is more abundant in the folds of the body (elbow, axillary, inguinal, etc. folds).

Development of internal genital organs continues: boys have the scrotum, girls have the ovaries.

Respiratory frequency increases up to 50-60 times per minute.

The swallowing reflex is still well developed: the child constantly swallows amniotic fluid with particles of protective skin lubricant. The liquid part of the amniotic fluid is absorbed into the blood, leaving a thick green-black substance (meconium) in the intestines. Normally, the bowel should not have a bowel movement until the baby is born. Sometimes swallowing water causes hiccups in the fetus; a woman can feel it in the form of rhythmic movements for several minutes.

Twenty-fourth week (162-168 days)

By the end of this week, the weight of the fetus increases to 600 grams, body length to 30-32 cm.

The movements are becoming stronger and clearer. The fetus takes up almost all the space in the uterus, but can still change position and turn over. Muscles grow rapidly.

By the end of the sixth month, the child has well-developed sense organs. Vision begins to function. If a bright light hits a woman’s belly, the fetus begins to turn away and closes her eyelids tightly. Hearing is well developed. The fetus determines pleasant and unpleasant sounds for itself and reacts to them differently. When hearing pleasant sounds, the child behaves calmly, his movements become calm and measured. When unpleasant sounds occur, it begins to freeze or, conversely, moves very actively.

An emotional connection is established between mother and child. If a woman experiences negative emotions (fear, anxiety, melancholy), the child begins to experience similar feelings.

Fetal development in the seventh obstetric month (25-28 weeks)

Twenty-fifth week (169-175 days)

The length of the fetus is 30-34 cm, body weight increases to 650-700 grams. The skin becomes elastic, the number and severity of folds decreases due to the accumulation of subcutaneous fatty tissue. The skin remains thin with a large number of capillaries, giving it a red color.

The face has a familiar appearance to a person: eyes, eyelids, eyebrows, eyelashes, cheeks, ears are well defined. The cartilage of the ears remains thin and soft, their bends and curls are not fully formed.

Bone marrow develops intensively, which takes on the main role in hematopoiesis. The fetal bones continue to strengthen.

Important processes occur in lung maturation: small elements of lung tissue (alveoli) are formed. Before the baby is born, they are without air and resemble deflated balloons, which straighten out only after the first cry of the newborn. From week 25, the alveoli begin to produce a special substance (surfactant) necessary to maintain their shape.

Twenty-sixth week (176-182 days)

The length of the fruit is about 35 cm, the weight increases to 750-760 grams. The growth of muscle tissue and subcutaneous fat continues. Bones are strengthened and permanent teeth continue to develop.

The formation of genital organs continues. In boys, the testicles begin to descend into the scrotum (the process lasts 3-4 weeks). In girls, the formation of the external genitalia and vagina is completed.

Improved sense organs. The child develops a sense of smell (smell).

Twenty-seventh week (183-189 days)

Weight increases to 850 grams, body length - up to 37 cm.

The organs of the endocrine system are actively functioning, in particular the pancreas, pituitary gland and thyroid gland.

The fruit is quite active, makes freely various movements inside the uterus.

From the twenty-seventh week in the child individual metabolism begins to form.

Twenty-eighth week (190-196 days)

The child’s weight increases to 950 grams, body length – 38 cm.

By this age the fetus becomes practically viable. In the absence of organ pathology, the child good care and treatment can survive.

Subcutaneous fat continues to accumulate. The skin is still red in color, the vellus hair begins to gradually fall out, remaining only on the back and shoulders. Eyebrows, eyelashes, and hair on the head become darker. The child begins to open his eyes frequently. The cartilage of the nose and ears remains soft. The nails do not yet reach the edge of the nail phalanx.

This week starts more one of the cerebral hemispheres is actively functioning. If the right hemisphere becomes active, then the child becomes left-handed; if the left hemisphere becomes active, then right-handedness develops.

Fetal development in the eighth month (29-32 weeks)

Twenty-ninth week (197-203 days)

The weight of the fetus is about 1200 grams, the height increases to 39 cm.

The baby has already grown enough and takes up almost all the space in the uterus. Movements become less chaotic. The movements manifest themselves in the form of periodic kicks with the legs and arms. The fetus begins to take a definite position in the uterus: head or buttocks down.

All organ systems continue to improve. The kidneys already secrete up to 500 ml of urine per day. The load on the cardiovascular system increases. The blood circulation of the fetus is still significantly different from the blood circulation of the newborn.

Thirtieth week (204-210 days)

Body weight increases to 1300-1350 grams, height remains approximately the same - about 38-39 cm.

Subcutaneous fat tissue constantly accumulates, skin folds straighten out. The child adapts to the lack of space and takes a certain position: curls up, arms and legs crossed. The skin still has a bright color, the amount of grease and vellus hair decreases.

Alveolar development and surfactant production continues. The lungs prepare for the birth of the baby and the start of breathing.

Brain development continues brain, the number of convolutions and the area of ​​the cortex increases.

Thirty-first week (211-217 days)

The child's weight is about 1500-1700 grams, height increases to 40 cm.

Your child's sleep and wake patterns change. Sleep still takes a long time, during which time there is no motor activity of the fetus. While awake, the child actively moves and pushes.

Fully formed eyes. During sleep, the child closes his eyes, while awake, the eyes are open, and the child blinks periodically. All children have the same iris color ( blue color), then after birth it begins to change. The fetus reacts to bright light by constricting or dilating the pupil.

Brain size increases. Now its volume is about 25% of the volume of the adult brain.

Thirty-second week (218-224 days)

The child's height is about 42 cm, weight - 1700-1800 grams.

Accumulation of subcutaneous fat continues, due to which the skin becomes lighter, there are practically no folds left on it.

Internal organs are improved: organs of the endocrine system intensively secrete hormones, surfactant accumulates in the lungs.

The fetus produces a special hormone, which promotes the formation of estrogen in the mother’s body, as a result, the mammary glands begin to prepare for milk production.

Fetal development in the ninth month (33-36 weeks)

Thirty-third week (225-231 days)

The weight of the fetus increases to 1900-2000 grams, height is about 43-44 cm.

Skin becomes increasingly lighter and smoother, the layer of fatty tissue increases. The vellus hair is increasingly wiped off, and the layer of protective lubricant, on the contrary, increases. Nails grow to the edge of the nail phalanx.

The baby becomes increasingly cramped in the uterine cavity, so his movements become more rare, but strong. The position of the fetus is fixed (head or buttocks down), the likelihood that the child will turn over after this period is extremely small.

The functioning of internal organs is becoming more and more improved: the mass of the heart increases, the formation of the alveoli is almost complete, the tone of the blood vessels increases, the brain is fully formed.

Thirty-fourth week (232-238 days)

The child's weight ranges from 2000 to 2500 grams, height is about 44-45 cm.

The baby now occupies a stable position in the uterus. The bones of the skull are soft and mobile thanks to the fontanelles, which can close only a few months after birth.

Head hair grows rapidly and take on a certain color. However, hair color may change after childbirth.

Intensive strengthening of bones is noted, in connection with this, the fetus begins to take calcium from the mother’s body (the woman may notice the appearance of seizures at this time).

The baby constantly swallows amniotic fluid, thereby stimulating the gastrointestinal tract and the functioning of the kidneys, which produce at least 600 ml of clear urine per day.

Thirty-fifth week (239-245 days)

Every day the child gains 25-35 grams. Weight during this period can vary greatly and by the end of the week it is 2200-2700 grams. Height increases to 46 cm.

All internal organs of the child continue to improve, preparing the body for the upcoming extrauterine existence.

Fatty tissue is intensively deposited, the child becomes more well-fed. The amount of vellus hair is greatly reduced. The nails have already reached the tips of the nail phalanges.

A sufficient amount of meconium has already accumulated in the fetal intestines, which normally should go away 6-7 hours after birth.

Thirty-sixth week (246-252 days)

The weight of a child varies greatly and can range from 2000 to 3000 grams, height - within 46-48 cm

The fetus already has well-developed subcutaneous fatty tissue, skin color becomes lighter, wrinkles and folds disappear completely.

The baby occupies a certain position in the uterus: more often he lies upside down (less often, with his legs or buttocks, in some cases, transversely), his head is bent, his chin is pressed to his chest, his arms and legs are pressed to his body.

Skull bones, unlike other bones, remain soft, with cracks (fontanelles), which will allow the baby's head to be more pliable when passing through the birth canal.

All organs and systems are fully developed for the existence of a child outside the womb.

Fetal development in the tenth obstetric month

Thirty-seventh week (254-259 days)

The child's height increases to 48-49 cm, weight can fluctuate significantly. The skin has become lighter and thicker, the fat layer increases every day by 14-15 grams per day.

Cartilages of the nose and ears become denser and more elastic.

Fully lungs are formed and mature, the alveoli contain the necessary amount of surfactant for the newborn to breathe.

The digestive system has matured: Contractions occur in the stomach and intestines to push food through (peristalsis).

Thirty-eighth week (260-266 days)

A child's weight and height vary greatly.

The fetus is fully mature and ready to be born. Externally, the child looks like a full-term newborn. The skin is light, the fatty tissue is sufficiently developed, and vellus hair is practically absent.

Thirty-ninth week (267-273 days)

Typically two weeks before birth the fruit begins to descend, pressing against the pelvic bones. The child has already reached full maturity. The placenta begins to gradually age and its metabolic processes deteriorate.

The weight of the fetus increases significantly (30-35 grams per day). The proportions of the body change completely: the chest and shoulder girdle are well developed, the belly is round, and the limbs are long.

Well developed sense organs: the child catches all sounds, sees bright colors, can focus his vision, and taste buds are developed.

Fortieth week (274-280 days)

All indicators of fetal development correspond to new to the awaited one. The baby is completely ready for birth. The weight can vary significantly: from 250 to 4000 and above grams.

The uterus begins to periodically contract(), which is manifested by aching pain in the lower abdomen. The cervix opens slightly, and the fetal head is pressed closer to the pelvic cavity.

The skull bones are still soft and pliable, which allows the baby’s head to change shape and pass the birth canal more easily.

Fetal development by week of pregnancy - Video

(See interpretation: trees or by name)

Seeing many different fruits in a dream means that many pleasant experiences await you and you will have many sources of income and enjoy everyday joys and love pleasures. Seeing a lot of fruits in a dream festive table portends good luck in business. Sweet fruits in a dream foretell joy and wealth. If in a dream the fruits are sour, unripe, rotten or bitter, then events await you that will make the same impression on you as the taste of the fruits that you ate in the dream. As a rule, such dreams foreshadow grief, business failures, disappointments and losses. A dream about rotten fruits is very important, which sometimes predicts misfortune or death of children. Unripe fruits in a dream often portend illness, and picking or seeing a green fruit (or fruits) is a sign of making a hasty decision. Often such a dream indicates that you may make a mistake when starting to implement your plan, which requires improvement.

If the fruits you pick are overripe, then the dream indicates to you that your delay will ruin the business you have started and you are hopelessly late in implementing your project. Fruits on trees are a sign of great wealth and profit. Harvesting, seeing fruits stacked in baskets or boxes in a dream, shaking fruit trees foretells good earnings from a profitable business. Artificial fruits in a dream mean that you will learn about deception or loss.

Interpretation of dreams from the Family Dream Book

Dream Interpretation - Male Self

He is the embodiment of logic, intellect, and spirit of consciousness.

In archaic societies this principle is less developed than in civilized societies.

So-called modern man strives for excessive discrimination, totalitarianism, quickly becomes, having power, overly critical and unfair, moralizes and goes astray into dry intellectualization.

This process is repeated again and again in each subsequent generation.

There are four main aspects of realization in the male self, each of which relates to one of the four functions of consciousness: father (affect); eternal youth (emotions); hero (intelligence); magician (intuition).

Interpretation of dreams from