Design and implantation of the egg The design begins at the meeting between the egg and sperm. Cell division begins. Upon his arrival in the uterus , the egg floats freely again before settling there , about 7 days after fertilization: the implantation. The placenta and umbilical cord begin to develop against the uterine lining.
Hormonal level , it is the joint action of progesterone , estrogen and corpus luteum hormone HCG allows implantation and the successful development of the egg.
1 month: from egg to embryo About the 15th day , we can already see the outline of the digestive system , and five days later , the cardiac tube , already bustling spasmodic contractions. The first sexual cells and appear at the end of the first month , it measures 5 mm.
The second month: the completion of embryogenesis This is the beginning of the 2nd month appear the members in the form of small shoots , and drafts of the face. The nervous system develops in parallel with devices urinary , digestive , respiratory and sexual. Ossification begins. At the end of the second month , the embryo's head is raised , the trunk is straight , it measures 3 cm. Embryogenesis is completed: the draft all organs are formed.
3rd month: from embryo to fetus The third month marks the differentiation of sexual organs. Because even if the egg at fertilization was scheduled to be a boy or girl , genitals was not yet formed. During the third month , the face also becomes more human members lengthen the muscles and joints develop.
At the 12th week , the first ultrasound monitoring to verify the proper development of the embryo , now known as fetus. It measures about 10 cm.
The fourth month: stride During the fourth month , the head is less disproportionate to the rest of the body. Skin , fine , lets see small vessels. The liver and kidneys begin to function , urine flowing into the amniotic fluid. The first hair appears.
5th month: it moves! Even if the fetus was moving a lot , it was during the 5th month in general , that the mother can feel. Approximately 25 cm to 500 g , fat-free body is covered with a wrinkled skin. His brain has a smooth surface devoid yet recesses (grooves) and bumps that will characterize later.
During the fifth month , on the second practical ultrasound control (morphological). You can usually find out the sex of the baby.
6th month: the development of hearing In the sixth month , the fetus becomes progressively viable extrauterine environment. The brain continues to mature , the body matures , the face shape. The baby moves a lot , responds to external sounds and emotions of his mother. At the end of the sixth month , the fetus is more than 30 cm and weighs about 1 kg.
The seventh month: the senses The fetus is now also sensitive to light and forms. His eyes are open and functional , they may follow strong light source near the womb. It is viable , but it has not yet mature enough to adapt easily to the outside world.
At the end of the seventh month , on the third and final practice ultrasound control. The fetus is more than 40 cm and weighs 1.7 kg.
8th month: it grows A layer of fat under the skin form the fetus. Most of its organs already functioning , except liver and lungs , which will mature at the end of the eighth month.
If the brain was smooth at the end of the fifth month , at the end of this month 8 folds that allow it to properly route. The baby often already upside down , preparing for childbirth. It measures 45 cm and weighs 2.5 kg.
The ninth month: the final stretch The baby does not move much because the place lacks. He ended his lung maturation , gains weight and grows a little more. All his organs are functioning. His brain is preparing to face new sensations and learning which will continue to grow. The baby is considered term exactly 8 months and 1 week of gestation , 39 weeks (or 41 weeks of gestation). But it is perfectly viable from the 35th week of gestation (or 37 weeks). Its weight is only lower than if he had reached the correct term.
