Stages of human fetus formation.

 Changes week by week!

Pregnancy is defined as the period between the inception of the fetus (fertilization) and birth, that is, during the growth and development of the child in the mother's womb.

And because it is impossible to know exactly when the fetus was conceived; The gestational age is calculated from the first day of the mother's last menstrual period.

It is calculated in weeks.

This means that during the first and second weeks of pregnancy, a woman in it is not yet pregnant.

This is when her body prepares to receive the fetus.

A normal pregnancy lasts for 37 to 41 weeks.

Week 1 - 2:

The first week of pregnancy is from the first day of a woman's menstrual cycle and she is not considered pregnant yet.

- At the end of the second week, the egg is secreted from the ovary, and this is at the most likely time for pregnancy if sexual intercourse takes place without contraception.

Week 3:

sperm.

During sexual intercourse, after the man ejaculates, sperm enter the vagina.

Week 4:

Once the blastocyst reaches the uterus, it implants itself into the uterine wall.

At this point in a mother's menstrual cycle, the uterine lining is thick and full of blood, ready to support the baby.

The blastocyst attaches firmly to the uterine wall and receives nourishment from the mother's blood.

Week 5:

- The fifth week is the beginning of the “embryonic period,” which is the period during which all the basic organs of the child begin to form.

The stronger sperm will continue the path to the cervix (entrance to the womb), and then to the fallopian tube.

A single sperm from the father and an egg from the mother meet in the fallopian tube.

By the time the sperm enters the egg, fertilization takes place.

The sperm and the egg together are called the zygote.

The zygote carries all the genetic information (DNA) needed for a baby.

Half of it comes from the mother's egg and the other half from the father's sperm.

The zygote spends the next few days on its journey to descend into the fallopian tube.

During this time, it divides to form a globule of cells called a blastocyst.

A blastocyst consists of an inner group of cells covered by an outer shell.

The inner group of cells will grow into a fetus.

The fetus is what will grow and be your baby.

The outer group of cells will turn into compounds called membranes, which nourish and protect the fetus.

The cells of the fetus divide and begin to take on a specific function. This is called appropriation (epigenetic) (differentiation).

Blood cells, kidney cells, and nerve cells are made.

The fetus grows rapidly, and the external features of the fetus begin to form.

Your baby's brain, spinal cord and heart are starting to form.

Your baby's digestive system is starting to develop.

During this time in the first trimester, the baby is at risk of harm and birth defects.

This includes some types of medication, drug addiction, excessive alcohol consumption, infection such as rubella, and other factors.

Week 6-7:

Arm and leg buds begin to grow.

Your baby's brain begins to specialize into five parts, and some cranial nerves.

Eyes and ears begin to form.

Tissue grows to form the spine, as well as some bones.

Your baby's heart continues to grow and starts beating regularly.

Blood rushes into the main vessels.

Week 8:

The arms and legs are longer.

The feet and hands form and look like paddles.

Your baby's brain continues to grow.

The lungs begin to form.

Week 9:

The nipples and hair follicles are formed.

The arms grow and the elbow joint (elbows) develop.

Baby's fingers begin to grow and you can see them.

All of a child's major organs begin to grow.

Week 10:

- Your baby's eyelids are now more developed and can be applied to the eyes.

The outer ears begin to form.

The external features of the child's face become clearer.

The intestine is wrapped.

- At the end of the tenth week, your baby is not yet an embryo, it is now a fetus, the stage of development until birth.

Week 11-14:

Your baby's eyelids clench and won't reopen until week 28 of pregnancy.

- Your baby's face is elaborately formed.

Limbs are long and thin.

The appearance of nails on the fingers and toes.

- The genitals appear.

The head is very large, about half the size of a child.

Your little one is now able to grip with his hands.

Tooth buds appear.

Week 15-18:

At this stage, the baby's skin is almost transparent.

He has fine hairs called villi growing on his head.

Muscle and bone tissue continues to grow, and bones become stiffer.

Baby begins to move and stretch.

The liver and pancreas begin to secrete.

Your little one can now gesture to sucking or feeding.

Week 19-21:

Your baby can now hear.

Your baby is now more active and continues to move and float around.

The mother may feel some strokes in the lower abdomen. This is called fetal movement, when the mother feels it for the first time.

By the end of this week, the fetus can swallow.

Week 22:

The fluff (thin hair) covers the entire body of the child.

Meconium is a dark substance that forms inside the intestine of a fetus.

Eyebrows appear, eyelashes appear.

The baby is now more active, with more muscle growth.

A mother can feel the movement of her baby.

Nails grow to the end of the fingers.

Week 23-25:

The lower parts of the respiratory system grow inside the baby's lungs.

The baby begins to store fat.

Week 26:

Eyebrows and eyelashes are well formed.

All parts of your baby's eyes are fully developed.

Loud noises and noises can frighten your baby.

Fingerprints on the hands and feet.

The air sacs are inside the baby's lungs, but the lungs are not yet ready to work outside the womb.

Week 27-30:

Baby's brain grows rapidly.

The child's nervous system is growing enough to control some body functions.

The child's respiratory system begins to secrete surfactant. This material helps the air sacs fill with air easily.

Week 31-34:

Your baby is growing faster and starting to gain weight.

Your baby starts breathing in an orderly fashion, but his lungs are not ready yet.

Your baby's bones are fully developed, but still soft.

Your baby's body begins to store iron, calcium and phosphorous.

Week 35-37:

The baby weighs approximately 5.5 pounds (2.5 kilograms).

Your baby continues to gain weight, but most likely he will not continue to gain height.

The skin is not wrinkled due to the accumulation of fat underneath.

A child has a known sleep pattern.

Your little one's heart is complete with all arteries and veins.

Musculoskeletal are fully developed.

Week 38-40:

The fluff disappears except on the upper arms and shoulders.

Nails grow longer than the tip of a finger.

Small breast buds appear in both sexes.

At your 40th week of pregnancy, it will be 38 weeks since conception, and your baby can be born any day.