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

2024 Author: Priscilla Miln | [email protected]. Last modified: 2023-12-16 00:21

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 a rich life of an unborn baby is going on inside a woman.

For an 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.

First to fourth weeks of fetal life

After the fusion of the egg with the sperm in seven days, 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 villi of the embryo with blood vessels. This begins the formation of the umbilical cord and membranes.

From the second week, the foundation of the neural tube begins to form in the fetus - this is the structure that is the main link in the central nervous system. The embryo is fully attached 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 on the 21st day it begins to beat. The fetal cardiovascular system is formedthe first and serves as the basis for the full-fledged birth of new organs.

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

Embryo growth in the second obstetric month

During the fifth week 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 formation of sex in the fetus occurs. Although it will be possible to determine whether a boy or a girl will be born much later.

During the sixth week, the development of the cerebral cortex continues, facial muscles begin to appear. The basis of the fingers and nails is formed. The heart is divided into two chambers, followed by the ventricles and atria. The liver and pancreas are practically formed. The weight of the fetus by weeks of pregnancy changes 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 nutrients are supplied to the fetus with its help. The embryo can already open its mouth, eyes and fingers have appeared.

The following changes occur with the fetus this month:

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

Fetal life from 9 to 12 weeks

BecauseSince the embryo receives nutrients from the woman’s blood, the development of the fetus by weeks of pregnancy largely depends on what the expectant mother eats. Make sure you get enough protein in your body.

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

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

• sucking reflex is developed;
• the fetus can already turn its head;
• buttocks are forming;
• you can move your fingers;
• eyes continue to form

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

What happens to an 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, the blood type, Rh factor is determined;
• urination begins in the amniotic fluid;
• completely appeared toes, hands;
• nail plates formed;
• insulin begins to be produced;
• girls develop ovaries, boys prostate, but it is still difficult to determine the sex of the child on ultrasound

In a childswallowing and sucking reflexes appear. He can already clench his fists, make movements with his hands. The baby sucks his thumb 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, it can already be heard by the expectant mother.

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

At 19-20 weeks, the fetus sucks its thumb, learns to smile, wince, 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 child's immunity is strengthened by the synthesis of immunoglobulin and interferon.

Sixth month pregnant

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

The fetal brain continues to develop, neurons are working at full capacity. The heart muscle increases insizes, the vessels are improved. During this period, the baby learns to breathe, the number of inhalations and exhalations increases. The lungs have not yet completed their development, but alveoli are already forming on them.

The sixth month is significant in that at this time an emotional connection is established between the child and the mother. All the feelings experienced by a woman are transmitted to the baby. If a pregnant woman is afraid, then 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 baby's eyes and hearing are fully formed. He can already respond to various sounds.

Fetal development from 25 to 28 weeks

Fetal development 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 baby has a metabolism;
• cerebral hemispheres begin to function;
• sexual organs continue to develop;
• bones get stronger, baby can already smell;
• baby's eyelids open;
• formed fat layer;
• body covered with fluffy hairs

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

The eighth month of a baby's life in the womb

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

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

The fluff that has formed on the child's body gradually disappears during this period, instead a special lubricant is formed. The cheeks, arms, legs, hips, shoulders of a small person acquire roundness due to the accumulation of the necessary fat layer.

Scientifically proven that the baby can already dream. Since the baby's weight increases and it takes up almost all the space in the uterus, its activity decreases.

Fetus at 33 to 36 weeks of pregnancy

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

During 34 weeks, the baby grows hair, right now his body needs calcium so much for proper development and strengthening of bones. In addition, the child's heart increases, vascular tone improves.

At 36 weeks, the little man takes a positionin which his head, arms, legs are pressed against the body. By the end of this period, the child is fully mature for existence outside the womb.

Tenth Obstetric Month

Gynecologists and ordinary people have different opinions about how long a child is born. It is customary in society to talk about nine months, but doctors have their own calculation, the baby is born after ten obstetric months. One medical week is considered 7 days. Accordingly, there are only 28 days in the obstetric month. This is how the “extra” month comes on.

A photo of the fetus by week of pregnancy shows that the baby is ready for birth at the end of the term. His stomach contracts, thus proving the possibility of eating not through the umbilical cord. Baby can smell, hear sounds, taste.

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

About fourteen days before delivery, the baby descends. From now on, birth can come at any moment.

How the weight of the fetus changes by week of pregnancy

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

Weight is affected not only by the nutrients the baby receives, but also by genetic predisposition. If parents know how much they weighed at birth, then you can guess the size of the child.

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

Fetal height and weight chart

Week	Weight, g	Height, cm
1
2
3
4
5
6
7
8	1	1, 5
9	2	2, 4
10	4	3, 0
11	7	4, 0
12	14	5, 3
13	23	7, 3
14	44	8, 6
15	71	10, 0
16	100	11, 6
17	140	13, 0
18	192	14, 0
19	250	15, 0
20	300	25, 5
21	360	26, 7
22	440	27, 7
23	500	28, 9
24	600	30, 0
25	670	34, 5
26	750	35, 4
27	880	36, 6
28	1000	37, 5
29	1150	38, 6
30	1310	39, 8
31	1500	41, 0
32	1700	42, 3
33	1900	43, 7
34	2100	45, 0
35	2380	46, 0
36	2620	47, 1
37	2860	48, 5
38	3100	49, 8
39	3300	50, 6
40	3450	51, 2
41	3600	51, 3
42	3680	51, 7
43	3710	51, 7

The formation of the fetus by weeks of pregnancy shows that at the time close to childbirth, weight gain slows down, the growth of the child practically does not change.

In order for the baby to receive enough nutrients and develop normally, the expectant mother should pay attention to proper he althy nutrition. Try to exclude flour products, as excess weight gain can lead to he alth problems for the child.

Understanding how a fetus develops in the womb will help you avoid unnecessary worries and unnecessary fears.