The first month of pregnancy. Approximately 4 days after fertilization, the egg reaches the uterus. By this time she is a ball with a liquid containing about 100 kletok.V end of third week of the fertilized egg begins to take root in the soft wall of the uterus. This is only an egg implantatsiey.Kak securely fastened to the wall, the process of conception is considered complete.
The second and third months of pregnancy. Later, during the second and third months, there is a tab of all the internal organs and systems of the child.
By the end of the third month in each of the future is at least one cell, and the formation of the circulatory system is almost complete. The main body of the fetal blood from the 5th to the 20th week is the liver. The blood of the fetus on the composition differs significantly from the blood of a newborn baby. At the end of the third month of using ultrasound can listen to the baby's heartbeat, pulse, which is 130-150 beats per minute. Begins to form golosoobrazuyuschy apparatus. Muscles begin to function, and the kid does the first movement. He moves the arms and legs, jaws compresses, turns head, opens his mouth, trying to swallow and suck. The mother of these movements has not yet feels they are too weak.
The first movement, you can register with ultrasound (ultrasound) are already in 6-week fetus. Grasp reflex appears at 11-12 weeks, sucking in 13-14 weeks and 17 weeks the baby starts to blinks.
Formed external genitalia. The child's sex is determined at the time, when fused egg and sperm nuclei, and nothing can change it. However, the time the embryo keeps its secret. The fruit of "finds" with about half of the 9th to the 12th week.
Ends with the formation of the placenta. The placenta plays a leading role in the production of hormones needed to maintain pregnancy.
Previously, it engaged in so-called "corpus luteum of pregnancy," formed in place of mature eggs. It is believed that nausea, morning sickness, headaches, irritability, sometimes accompanied by a woman in the first trimester are due to the work of the "yellow body" for the removal of toxins from the body. In the cells of the placenta found enzymes to help prepare a special "dishes" for the fetus of the substances released from the mother's blood.
It is important to remember that with a lack of nutrients in the blood of the mother the fetus through the placenta takes them directly from the mother. Therefore, mother's diet should be full.
The growth of the fetus goes according to plan, given its genetic apparatus, and the organization of the placenta. If you do not have enough nutrients, the fetus begins to produce them for destruction by the maternal organism. However, the fetus is able to not only take but give. For example, if a pregnant woman suffers from diabetes (when the disease the pancreas reduces the production of the hormone insulin), the fetus begins to secrete insulin in abundance - for myself and for my mother. However, it is very harmful to an unborn baby, as overloads cancer baby! In this case, it is important to seek medical attention.