Mental retardation is not a disease itself. It cannot be cured and its not contagious(传染的). This condition can be caused by several things that injure the brain or dont allow the brain to develop normally. Many times we dont know why a person has mental retardation.
Sometimes it may be caused by genes. Genes are chemical units found in every cell. They carry the instructions telling cells what to do. Sometimes, children receive abnormal genes from their parents.
A defective gene may also develop spontaneously. Neither parent would have passed on the gene, but the gene changes before the baby develops.
Some other problems that can cause mental retardation also happen before a child is born. It is important for the brain to develop properly if a child is to have normal intelligence. Planning a pregnancy is the most important decision most of us will make in our lifetime. A healthy lifestyle and good medical care should begin before a woman becomes pregnant and continue throughout the pregnancy, says Jodi Rucquoi, a genetic counselor from Connecticut. If a woman abuses alcohol or drugs or doesnt eat well, there is a risk to the developing baby. Also, a premature birth or problems during childbirth can sometimes harm the babys developing brain. While premature babies are generally fine. There is a greater chance that they may have mental retardation.
In some cases, a young child can develop mental retardation after being sick with a serious infection or other illness, or after suffering a bad head injury.
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