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In 9 months a child goes a long way from a tiny embryo to a chubby baby. While in the womb, they already have some features that will remain with them for life, for example, you can tell if the baby will become right-handed or left-handed and which foods they will prefer. During a fairly short period of time there are a lot of interesting things that happen to a child, and today we suggest that you journey along with the baby from conception to birth.

Bright Side brings you this exciting tour.

1st trimester

Weeks 1–2

So the long journey has begun. For the first 4 days, this future person is smaller than a grain of salt — its size is only 0.005 in. However, starting from the 5th day, it begins to grow and by the 6th day it’s size nearly doubles — to as much as 0.01 in. On the 4th day the embryo “migrates” to where it will spend the next 9 months — the uterus, and on the 8th day it’s implanted into the wall.

Weeks 3–4

The above embryo is in the 4th week of pregnancy.

On approximately the 20th day of pregnancy a very important event occurs: a neural tube appears, which then turns into the upper back and brain of the child. On the 21st day, their heart already starts to beat and all of the important organs are formed like the kidneys and liver. The eyes have not yet taken their normal position — the bubbles, from which they will later be shaped, are on the sides of the head. By the end of the first month the embryo has a circulatory system, and the spine and muscles begin their development.

Weeks 5–6

In the 5th week, hands and wrists are developed by the embryo. Although it’s still very difficult to distinguish the fingers, the hands and legs are already able to bend at the joints. It’s at this time that the external genitalia begin to form, however it’s still impossible to see whether the baby is a boy or a girl. By the way, from the moment of its appearance the embryo has grown a lot — as much as 10 thousand times its original size. Also the baby’s face begins to form, and their eyes darken and become more humanlike, but will still be closed for a very long time.

Weeks 7–8

The 7th week of pregnancy is the time when the baby starts to move, but this is still not noticeable for the mother. Also, the fingers and toes on the arms and legs become almost the same as those of adults. At this stage, the embryo builds rudimentary infant teeth, further develops the reproductive system, and the kidneys begin to produce urine. Despite the fact that the size of the fetus is only 1 in, it’s already acquired its own facial expressions, it has eyelids, and the tip of its nose becomes more defined.

Weeks 9–10

This child is in the 9th-10th week of pregnancy.

By this time, the baby has already grown quite a bit — its weight is .15 oz, and its height is 1.2 in. Despite the tiny dimensions, the brain is already divided into two hemispheres, and the milk teeth and taste buds begin to form. The baby loses its tail and the membranes between the fingers, it begins to swim in the amniotic fluid, and move even more actively, although it’s still unnoticeable for the mother. It’s at this time that the child develops individual facial features and hair begins to grow on the head.

Weeks 11–12

At this time the child’s genitals are formed and you can already tell their gender via ultrasound, although the probability of error is still high. The child looks slightly alien: it has a large head and a small body, but its face looks even more like that of an adult. Ears have almost come to the right position and eyebrows and eyelashes appear too. Cartilage, which currently makes up the skeleton, gradually ossifies, new blood vessels appear, and the production of hormones begins. By the way, the baby has grown to 2.4 in and weighs about .7 oz.

Weeks 13–14

This child is in the 14th week of pregnancy.

Despite the fact that the child’s head is half the length of its entire body, the face looks even more developed, and the buds of all 20 milk teeth are already formed in the mouth. The child is able to put their finger in their mouth, but they won’t learn to suck it until a little later. Because of the active formation of the vessels, the skin of the baby is red and very thin, and lanugo hair appears on the body to help preserve a special lubricant that protects the baby from hypothermia.

2nd trimester

Weeks 15–16

By the 15th week the baby grows to 4 in long and gains more weight — now its about 2.5 oz. Despite the fact that the eyes are still low on the head the face is already recognizable and the child begins to “make faces,” because the facial muscles are well developed. By this time they already know how to suck their finger, and the sebaceous and sweat glands begin their work.

Weeks 17–18

Finally the the child forms their auditory canals, so they start to distinguish sounds well and are able to hear their mother’s voice, and even recognize it. In addition to the milk teeth, the permanent teeth buds appear, and the bones are finally formed and begin to harden. By the way, the bones of the skull will remain malleable until birth — when passing through the birth canal, they will be superimposed on each other to make the whole process easier. The mother is finally beginning to feel the movements of the child that has grown to 5.5 in and 6.7 oz.

Weeks 19–20

This child is in the 20th week of pregnancy.

Despite the fact that the child’s eyes are still closed, the baby is already able orient well in the surrounding space. Additionally, it’s now possible to understand whether the child is going to be right-handed or left-handed, because they are starting to use their leading hand more actively. There are also now fingerprints on the fingers of the baby — another unique sign to each of us. By the way, the child is beginning to distinguish day from night and shows signs of activity at certain times.

Weeks 21–22

The 21st week is the time when the child starts really gaining weight by forming subcutaneous fat. Soon, wrinkles, which can be seen on newborns will appear on his arms and legs. By the 22nd week the neurons that will be with this person for life are formed in the brain. Very soon the child will open their eyes, as they are already trying to do it, and their eyeballs move almost like those of an adult.

Weeks 23–24

At the 23rd week the child may begin to have dreams and the face is so developed that, on ultrasound, you can determine which parent’s features the baby has inherited. Their skin becomes opaque, their eyes open, and they can already react to light. At this time, bright flashes can even scare them. By the 24th week the baby grows to almost 12 in, and its weight reaches 1 lb.

Weeks 25–26

At this time, the taste buds of the baby are finally formed and tasting the amniotic fluid can make them frown if they don’t like it. By the way, this is exactly how eating habits are formed — in our mother’s womb we already have favorite and dislikes when it comes to food. Very soon the child will learn to blink and can already see a little, for now though, very, very vaguely.

3rd trimester

Weeks 27–28

This child is in the 27-28th week of pregnancy.

If you get an ultrasound at this time, you’ll be able to see how the child smiles and intensively sucks their finger. At this time, the baby has their first “toy” — their own umbilical cord, and they are actively studying their own body. At the end of the 7th month of pregnancy, the child develops their own individual metabolism, which they will have all their life. The baby is already quite large— its weight reaches 2.5 lb, and its height is 14 in.

Weeks 29–30

This child is in the 30th week of pregnancy.

The layer of subcutaneous fat is increasing in size and the baby is getting more and more chubby and well-fed. In addition, they already know how to cry, cough, and even sometimes hiccup — this happens, most likely, when they swallow too much amniotic fluid. By the 30th week the child’s brain is already so developed that it’s capable of remembering and even analyzing information.

Weeks 31–32

At this time, this new person has all 5 senses and their daily regimen looks more and more like the one that they will follow after birth. The child hears all the organs of the mother working and knows her voice so well that immediately after birth they are able to distinguish her from all other people. The baby’s immune system begins to produce antibodies that will protect them from all sorts of infections that can be caught in the first days and even months after birth.

Weeks 33–34

Finally, the subcutaneous fat has been fully formed and the lanugo disappears from the fetus’s body. By this time, the child has grown a lot — their body length reaches 16 in, and the weight comes close to or even exceeds 4.5 lb. The infant’s nervous system is already fully formed, but the lungs are still developing.

Weeks 35–36

The child yawns. 3D-ultrasound at the 36th week of pregnancy.

At this time, the child looks almost exactly the same as when it’s born. The body is still rather thin, but the layer of subcutaneous fat increases more and more intensively. However, their hair and nails are already fully formed and the baby itself becomes so large that it has almost no room to move, so it may move less than in earlier stages.

Weeks 37–38

Finally, the process of the formation of a new human has come to an end — now the baby is completely ready for birth and midwives consider the pregnancy to be full-term. Lanugo completely disappears from the child’s body and only occasionally will remain on the hands and legs. Since there is almost no space left in the uterus, the mother may think that the child begins to move more intensively, in fact the force of the blows has increased, because the child’s muscles have fully formed and gotten stronger.

Weeks 39–40

The first minutes after birth.

The child’s lungs continue to form until birth and only at the moment of birth will they secrete the right amount of surfactant — a substance that prevents the alveoli from sticking together after the first independent breath. Very soon the baby will announce its birth with the first cry and begin its long journey through a large and interesting world.

Did you learn something new from this tour? Make sure to tell us what you think about it!

Preview photo credit East News, lunar caustic/wikimedia