The formation of the fetus by weeks of pregnancy. Fetal development by week

The birth and intrauterine development of a new person is a complex but well-coordinated process. The formation of the fetus by weeks shows that inside the woman, an intense life passes through the still unborn baby.

For the embryo every day is a new stage of development. A photo of the fetus by weeks of pregnancy proves that every day the fetus becomes more and more like a person and goes through a difficult path for this.

The first to fourth weeks of fetal life

After the egg and the sperm merge, seven days later, a new organism is implanted in the uterine cavity. The formation of the fetus from the moment of conception begins with the connection of the fibers of the embryo with the blood vessels. This serves as the beginning of the formation of the umbilical cord and membranes.

From the second week, the basis of the neural tube begins to be laid in the fetus - this is the structure that is the main link in the central nervous system. The embryo is completely fixed to the walls of the uterus for further development and nutrition.

The formation of the heart in the fetus occurs in the third week and already at 21 days it begins to beat. The cardiovascular system of the embryo is formed first and serves as the basis for the full nucleation of new organs.

The fourth week is marked by the launch of blood circulation in the fetus. Organs such as the liver, intestines, lungs, and spine begin to form.

Embryo growth in the second obstetric month

During the fifth week, the following are formed:

• eyes, inner ear;
• nervous system;
• the circulatory system develops;
• pancreas;
• digestive system;
• nasal cavity;
• upper lip;
• rudiments of limbs

In the same period, the fetal sex is formed. Although it will be possible to determine whether a boy or girl is born much later.

During the sixth week, the development of the cerebral cortex continues, facial muscles begin to appear. The base of the fingers, nails is formed. The heart is divided into two chambers, the next turn of the ventricles and atria. The liver, pancreas are almost formed. The weight of the fetus by weeks of pregnancy does not change slightly at first, the active growth of the embryo begins from the fourth month.

The seventh week is significant in that the umbilical cord has completed its formation completely, now the nutrients enter the fetus with its help. The embryo can already open its mouth, eyes and fingers appear.

This month, the following changes occur with the fetus:

• a nasal fold appears;
• ears, nose begin to develop;
• the membrane between the fingers disappears

Fetal life from 9 to 12 weeks

Since the embryo receives nutrients from the blood of a woman, the development of the fetus by weeks of pregnancy largely depends on what the expectant mother eats. Adequate intake of protein should be taken care of.

During the ninth week, the fetus forms joints of the fingers and hands. The endocrine system is developing, which in the future will provide the basis for the appearance of the adrenal glands.

10-11 weeks of embryo life are characterized by the following stages:

• a sucking reflex is produced;
• the fetus can already turn its head;
• buttocks are formed;
• an opportunity to move your fingers;
• eyes continue to form

The twelfth week is characterized by the development of the genital organs, the fetus tries to make respiratory movements. The nervous and digestive systems continue to develop.

What happens to the embryo in the fourth month of pregnancy

The formation of the fetus by weeks during the fourth month is as follows:

• eyes, ears, nose, mouth are already clearly visible on the face;
• in the circulatory system, a blood group, Rh factor is determined;
• urination begins in the amniotic fluid;
• toes and arms fully appeared;
• formed nail plates;
• insulin begins to be produced;
• in girls, ovaries form, in boys - the prostate gland, but it is still difficult to determine the sex of the child by ultrasound

The child has swallowing and sucking reflexes. He can already clench his fists, make movements with his hands. The kid sucks a finger and can swim in the amniotic fluid. This is his first habitat. It protects the child from damage, takes part in the metabolism, gives a certain freedom of movement.

By the end of the fourth month, the baby’s eyes open, the retina continues to form.

17 - 20 weeks of fetal growth

During the seventeenth week, the baby begins to hear sounds. The heartbeat intensifies, the future mother can already hear it.

The development of the fetus by weeks of pregnancy is an energy-intensive occupation, therefore, during the eighteenth week, the child sleeps almost all the time and occupies an upright position. During his wakefulness, a woman begins to feel tremors.

At 19-20 weeks, the fetus sucks a finger, learns to smile, frown, close its eyes. Formed adrenal glands, pituitary gland, pancreas.

During this period, the baby’s head has a disproportionate size, this is due to the dominant formation of the brain. The immunity of the child is strengthened by the synthesis of immunoglobulin and interferon.

Sixth month of pregnancy

The formation of the fetus by the weeks of the sixth month is marked by an increase in the time when the child is awake. He begins to show interest in his body. This consists in touching the face, tilting the head.

The brain of the fetus continues its development, neurons work in full force. The heart muscle increases in size, the vessels improve. During this period, the baby learns to breathe, the number of inspirations and expirations increases. The lungs have not yet completed their development, but alveoli already form on them.

The sixth month is significant in that at this time the emotional connection of the child and the mother is established. All feelings experienced by a woman are transmitted to the baby. If the pregnant woman is afraid, the fetus will also begin to behave anxiously. Therefore, it is recommended that the expectant mother avoid negative emotions.

At the twenty-fourth week, the child's eyes and hearing are fully formed. He can already respond to various sounds.

Fetal development from 25 to 28 weeks

The development of the fetus by weeks of pregnancy from 25 to 28 is characterized by the following changes:

• lung tissue is formed, the lungs begin to produce surfactant - a substance that is aimed at reducing excessive stress in these organs;
• the child has a metabolism;
• cerebral hemispheres begin to function;
• genitals continue their development;
• bones become stronger, the child can already smell;
• baby's eyelids open;
• fatty layer is formed;
• the body is covered with hairs in the form of a gun

At a period of seven and a half months, the fetus can already be born, while the chance of survival is very high. But with premature birth, the mother's body has not yet developed the necessary amount of antibodies for the baby, so the resistance to disease in such a child will be low.

The eighth month of the baby’s life in the womb

The formation of the fetus by the weeks of the eighth month is due to the development of almost all organs. The cardiovascular system improves blood circulation, the endocrine system produces almost all hormones. In the child’s body, self-regulation of sleep and wakefulness occurs.

Due to the fact that a hormone is produced in the baby's body, which favors the increased production of estrogen in the expectant mother, her mammary glands are prepared for the formation and production of milk.

The cannon that has formed on the child’s body gradually disappears during this period; instead, a special lubricant forms. The cheeks, arms, legs, hips, shoulders of a small person gain roundness due to the accumulation of the necessary fat layer.

Scientifically proven that the baby can already see dreams. Since the weight of the child increases and it occupies almost the entire space in the uterus, its activity decreases.

Fetus at 33 to 36 weeks of gestation

The formation of the fetus during this period is approaching the final stage before childbirth. His brain is actively functioning, internal organs work almost like an adult, nails are formed.

During 34 weeks, the baby grows hair, right now his body so needs calcium to properly develop and strengthen bones. In addition, the heart of the child increases, the tone of the vessels improves.

At week 36, a small person occupies a position in which his head, arms, legs are pressed against his body. By the end of this period, the child is fully ripe for existence outside the womb.

Tenth obstetric month

Gynecologists and ordinary people have different opinions about how much time a child carries. It is customary in society to talk about nine months, but doctors have their own count, a baby is born after ten obstetric months. One medical week is considered 7 days. Accordingly, in the obstetric month only 28 days. And so the "extra" month runs up.

A photo of the fetus by weeks of pregnancy shows that the baby is ready for birth at the end of the term. His stomach contracts, thereby proving the possibility of eating food not through the umbilical cord. The kid can smell, hear sounds, distinguish taste.

The brain is formed, the necessary amount of hormones is produced in the body, the metabolism is established in the cycle necessary for the fetus.

About fourteen days before birth, the baby lowers. From this moment on, birth can come at any moment.

How does fetal weight change by week of pregnancy

Checking the weight of the fetus throughout pregnancy is very important. Any deviation from the norm may indicate violations in the development of the child.

Not only the nutrients supplied to the baby affect the weight, but also the genetic predisposition. If parents know how much they weighed at birth, then we can assume the size of the child.

The table below shows the weight and height of the child by week.

Table height and weight of the fetus

The formation of the fetus by weeks of pregnancy shows that at periods close to childbirth, weight gain slows down, the baby's growth remains almost unchanged.

So that the baby receives a sufficient amount of nutrients and develops normally, the expectant mother should pay attention to proper healthy nutrition. Try to exclude flour products, since exceeding the norm of weight gain can lead to problems with the health of the child.

Understanding how the fetus develops in the womb will help to avoid unnecessary fears and unnecessary fears.