The effects of Smoking for a child
Smoking decreases the reproductive ability. Smoking during pregnancy threatens harmful effects to the fetus. Also Smoking increases the risk of spontaneous abortion, it can cause fetal death or a newborn baby, the sudden infant death syndrome. Effect of Smoking during pregnancy is developmental delay and mental retardation children. According to the doctors, women who smoked during pregnancy had babies weighing on average, 170 g less than Nonsmoking women. This comes from the fact that the reduced blood circulation in the placenta and uterus.
In women with addictions, children are born with smaller brain volume
American scientists found that women who during pregnancy used tobacco, alcohol or take drugs are more likely to give birth to a child with a smaller volume of the brain. To such conclusions researchers came after examining the brains of 35 children aged 10 to 14 years. After that, and it was found that those children whose mothers during pregnancy continued to smoke, used alcohol, cocaine, Smoking tobacco or marijuana, significantly smaller head circumference, smaller brain volume, and they have less content of nerve cells, compared with peers whose mothers led a healthy lifestyle.
Dr. Michael George, author of the study, noted that in cases when the mother during pregnancy had only one bad habit, deviations from the norm the child was not very significant, but if these habits were some, on the brain of the unborn child's influence was much more impressive.
Chromosomal abnormalities — a major cause of spontaneous abortion. According to the latest Chromosomal abnormalities there are approximately 10% of fertilized oocytes and 5-6% of the fruit. Generally, chromosomal abnormalities cause miscarriage at 8-11 weeks of pregnancy, and can also be the main cause of late spontaneous abortion and stillbirth. Trisomy (47 chromosomes) is the most common chromosomal disorder that causes early spontaneous abortion. Followed by monosomy (45 chromosomes) and triploidy (69 chromosomes). The loss of the Y or second X chromosome is strongly violated in the development of an organism. If this did not lead to a spontaneous abortion, newborn (only girls) identify symptoms of Turner syndrome. Sometimes chromosomal aberrations find and seemingly perfectly healthy people with infertility, habitual abortion or when their children are born with congenital malformations.
Sudden infant death syndrome
Sudden death can occur from birth to 6 months. Reasons why there is a change in respiratory function several. During sleep muscle tone decreases, widening the upper airway, therefore, the permeability becomes smaller and increases the resistance of the latter. Decreases the sensitivity of the respiratory system, lost a stimulating influence on the respiratory center the state of wakefulness, slows the metabolism. Also in the dream of suppressed cough reflex. All the above factors play a role in the pathogenesis of sudden infant death syndrome.
Most often mental retardation more prevalent among men than among women, and the family nature of the disease it is usually characterized by mostly men. It is found that in some families mental retardation is inherited as X-linked trait. There are several such diseases. One of the most common of them is the fragile X chromosome, which is characterized by mental retardation, distinctive facial features and macroorchidism. This disease it is possible to identify cytogenetic methods. Usually a small part of the metaphase cells of the patient at the end of the long arm of the X chromosome (Xq28) has a "weak plot". The chromatin in this phase decondensation, and "brittle" due to the amplification of trinucleotide TSGG. Normally, the number of iterations in this phase from 2 to 50, and for patients it increases to 200 or more. It is believed that this amplification disrupts the function of neighboring genes, with the result that the disease evolves. Nowadays this syndrome is diagnosed using molecular genetic techniques.