...Genes on chromosome 21 that specifically contribute to the various symptoms of Down syndrome are now being identified. Down syndrome is typically caused by what is called nondisjunction. If a pair of number 21 chromosomes fails to separate during the formation of an egg (or sperm), this is referred to as nondisjunction. When that egg unites with a normal sperm to form an embryo, that embryo ends up with three copies of chromosome 21 instead of the normal two. The extra chromosome is then copied in every cell of the baby's body. Interestingly, nondisjunction events seem to occur more frequently in older women. This may explain why the risk of having a baby with Down syndrome is greater among mothers age 35 and older. In rare cases Down syndrome is caused by a Robertsonian translocation, which occurs when the long arm of chromosome 21 breaks off and attaches to another chromosome at the centromere. The carrier of such a translocation will not have Down syndrome, but can produce children with Down syndrome. Not everyone with these possible Down syndrome symptoms has the disorder. A number of these features can be seen in the general population, and these symptoms are common in other disorders. Physical characteristics of Down syndrome can include: A flat facial profile , An upward slant to the eye, A short neck ,...
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...risk the disease where blood sugar swings wildly in the child. As well as they can increase risk of developing a pregnancy difficulty seen as high blood pressure and signs of damage to another organ system, which usually are the organs that create urine. In addition, recent studies have also linked that a woman's pregnancy weight to her child's risk of breathing disease. Another effect and one of the most dangerous is that drinking alcohol during pregnancy can cause severe permanent mental problems in a baby (FAS). FAS is a born-with condition seen as mental and physical defects. Infants with FAS may experience withdrawal signs of jitteriness, irritability, and poor feeding within 12 hours after delivery. Another important effect and also very dangerous is smoking. Living in smoking surrounding conditions has long been tied to breathing disease and breathing problems in kids, even exposure to secondhand smoke in the womb may lead to health problems later on (Fetal). However, the most dangerous effects are drugs. Drug use during early pregnancy can affect the developing organs and limbs of the unborn baby. Even one episode of drug use during this period can affect the development of your child. In most cases, it results in a birth defect or miscarriage. Also later in pregnancy can affect the development of your baby's central nervous system. Medical care, procedures and tests constitute most of the things done during a woman’s pregnancy. Doctor’s appointments and visits are made...
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