human fetal development lasts about 270 days.This is the time during which a fertilized egg from developing a child ready for life outside the mother's body.Of course, a newborn baby is not yet independent - it needs constant care mother, special food and Conditions.However, during fetal development man reaches a certain level, which allows the body to maintain its temperature, and the constancy of the internal environment.
intrauterine growth is a single process that is in accordance with the genetic program of our species.During this time, the next kid goes through several important stages of formation.The value of each of them can hardly be overestimated.Currently, scholars have identified three stages of prenatal human development.
The first of these is called predembrionalnogo and lasts about two weeks.The beginning of fetal development is ripe the moment of fertilization of the egg.The menstrual cycle is a standard event occurs in the next day after ovulation ie on
second stage of fetal development called fetal.Its duration is 7-9 weeks, starting from 14 days after fertilization.During this time, the embryo of a few cells is transformed into a complex multicellular organism.The kid in its prenatal development repeats all the stages of the evolutionary formation of our species.During this period, formed and begin to function even the rudiments of all the major organs and systems of a child, is the formation of the skeleton, torso, head, upper and lower extremities.Furthermore, undergo changes and outer shell of the embryo.From the simplest trophoblast forms the most important organ of pregnancy - placenta.Its role is to provide a child's oxygen and nutrients from the maternal blood.A fully functioning placenta performs also the barrier function.She shares the bloodstream of mother and child, prevents the penetration of harmful substances, viruses, many immune factors to the embryo.At the end of this stage of fetal development baby already has a similar silhouette of a newborn and begins to be called a fruit.
next stage of fetal development called fetal.It starts after 12-14 weeks of pregnancy and should be completed by the appearance of a newborn baby born.This time is characterized by stable performance of the placenta, the rapid growth of the baby, the further improvement of organs and tissues.Fetal stage should ensure the establishment of functional systems that will support the independent life of the child after birth.In the last months before the birth of particularly intense accumulated fatty tissue, ripening enzyme systems of the body, the bones of the skeleton are developing.
fetal development normally completed in time for 38 to 42 weeks of pregnancy.When it will be born baby, it depends on each individual, and from the mother's body.
by week Prenatal development is studied well enough.Midwives, doctors of ultrasonic diagnostics, genetics use the information available to monitor the development of the baby during pregnancy.Fetal development by week often very interested and future mother.Reading about what changes are taking place with a child, she feels even more in touch with him.Fetal development are more stable, especially in the initial stages.This means that only after 28 weeks fetuses there are significant differences in the size and degree of operational readiness of organs and systems.Earlier this term babies look different mothers, and develop about the same.Thus, for example, 5 week all embryos occurs tab liver, pancreas, heart and upper respiratory tract.Already 6 weeks of fetal development the baby is heart beat.At the 9th week of the child's rapidly developing brain.With 10 weeks laid baby teeth and the external genitalia are formed.Genetic sex the baby is also determined at conception, but only to the 3-month fetuses begin to acquire obvious external differences.At the 11th week of fetal development are actively developing embryo fingers, lays the iris that determines their color.In a period of about 4 months the fetus appear nails, actively functioning bladder, bowel peristalsis is.With 26 weeks of intrauterine development of a baby begins to hear well, not only the mother's body sounds, but also of the world.With 30 weeks of the child's pupils are beginning to react to light and darkness.By week 33, the lungs should start actively to form a surfactant - a special substance that helps a person to breathe.In subsequent weeks of fetal development is actively improving the nervous system, and the baby continues to prepare for an early birth.
Proper prenatal development of human genetics is provided.This process is protected by a mass of mechanisms, but they sometimes give failures.Not everything depends on future parents.However, preparation for pregnancy, adherence of the day, proper nutrition expectant mother, calm psychological background is also largely determine the health of your baby.It is believed that, not yet being born, the child perceives the mother's emotions, reacts to them.Also important is the medical supervision of women.The doctor can assess the prenatal development of the child and to give all necessary recommendations.
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