The expectant mother, who is looking forward to the birth of her baby, is always interested in how her baby changes during pregnancy. Modern medicine knows almost everything about the conception and development of the fetus in the uterus. This allows you to find out what happens in each month of pregnancy.
Pregnancy develops 40 calendar weeks or 9 months, during which, according to a genetically programmed code, the organs and systems of the child are formed in several stages.
1-2 month
Morula, aka a fertilized egg, divides and goes into the uterine cavity. Having attached to its walls, the placenta begins to form from the blood vessels and villi, and the cells become the umbilical cord in the rudiment and soft tissues. A number of systems are laid in the embryo: circulatory, respiratory, digestive, excretory and one of the very first - nervous (from the neural tube).
Organs are formed: larynx and trachea, lungs, liver and kidneys, stomach and pancreas, intestines. On day 21, the heart begins to beat for the first time. By the end of the first month, the soft and wide layer in the shell will become the head, and folds will appear on the trunk. A chord is formed inside, from which the spine will develop. There are already muscles and the semblance of limbs. Depressions appear on the head - these are the eyes.
By the middle of the second month, the divisions of the brain and the ventricle with chambers and atria in the heart begin to be distinguished. Sex cells function. Through the umbilical cord between the uterus and the placenta, blood circulation has improved, the embryo receives nutrition and can breathe.
Facial features appear: lips and eyelids with which he moves under the influence of stimuli, as well as folds of the nose and ears. On the limbs - fused fingers with elastic nails. By the beginning of the third month, the body straightens, the embryo has become a fetus.
3-5 month
Bones appear, they become overgrown with cartilage and muscles, the child can clench his fingers into fists. The chin is still pressed against the chest, the neck has just begun to stretch. All systems change, continuing their formation: the intestine fits into loops, contracts for the first time, the adrenal glands work, erythrocytes and leukocytes are formed in the blood. The heart beats 150-170 beats per minute. Nerve endings have formed. The fetus is already moving, but the mother does not yet feel it.
By the end of the fourth month, facial features become clear, hair on the head and milk teeth appear. The genitals have developed: the ovaries in the small pelvis - in girls, the prostate gland - in boys. It's time to do an ultrasound. We can say that the fetus has already formed, further in the uterus it will mainly grow.
In the fifth month, his body is 15-20 cm long, he took an upright position, actively moves, sleeps and is awake in a certain mode. The skin and fatty tissue are formed. The heartbeat is listened to with a stethoscope. Basic reflexes and facial expressions appear.
6-9 month
The fetus spends a lot of time in a dream, it becomes cramped for it, so it bends its limbs. For the first time, the child begins to smell, hear and see, and his lungs have taken on a normal shape. The baby will be able to breathe on its own if born prematurely.
The formation of the genitals is complete, there are female and male genitals. The metabolism has improved. Preparing for birth forces the fetus to turn head down, cross its arms over the chest, press the knees against it and release a hormone that affects the production of milk by the mother's glands.
