Researchers have revealed that people residing in the vicinity of farms, which are sprayed with endosulfan, dicofol, or other organochlorine pesticides can give birth to babies suffering from autism. Mercury poisoning is another cause that, according to experts, has the potential to cause autism. The exact method in which mercury poisoning causes autism remains to be established through research.

During the first 8 weeks of pregnancy the fetus is more susceptible to develop autism. During this phase, exposure to elements like Thalidomide (a sedative used for a long time to cure morning sickness), Valproic acid (a constituent of various mood stabilizing drugs) and misoprostol (used in some anti-inflammatory drugs), may cause autism. Precisely how these agents cause the disorder is still being explored.

Experts have observed that when a pregnant woman suffers from thyroid disorders, there is a deficiency of thyroxin, a hormone, in her body. This in turn causes changes in the fetal brain and leads to autism in many cases. Experts advise that this can be averted by consuming iodine rich foods during pregnancy.

When a pregnant woman suffers from any infectious disease, the mother’s immune system is activated and Immunoglobulin G, which is an antibody that fights infections, is released into the body. If this antibody enters the fetus’ brain by crossing the placenta, it causes severe damage and this can result in autism and other neural development disorders.

Researchers also believe that bleeding, diabetes or intake of psychiatric drugs by a pregnant woman can cause autism. The first 8 weeks of pregnancy is the time when the risk factors are most likely to affect the fetus.

Most experts agree that autism affects a child in very early stages of development. Experts believe that autism can affect a fetus during pregnancy. Experts have proposed that older men, with greater genetic liability, marry and have children at a later stage in their life because they themselves have some traits of autism. The older the mother is, the more likely she is to develop pregnancy complications which can in turn cause autism.

Many people are more susceptible to autism due to a genetic predisposition. The heritability of this disorder is almost 90%. This signifies that there is a 90% chance that genetic causes are behind a person suffering from autism. Through linkage analysis and association analysis, experts have observed that one particular gene cannot be held as a causative agent.

There are a number of genes which can be a causative agent of autism and experts are yet to identify the specific mutations of the genes that increase the risk of autism. Experts now believe that parental genes can be responsible for a fraction of the disease, but they are certainly not the only causative factor. Experts have come to this conclusion because the specific mutations found in autistic patients have not been found in their parents, so now it is believed that a genetic predisposition toward autism can be inherited but the mutation occurs in the patient’s own body, when the genes react to environmental factors. So, genetic as well as environmental factors are responsible for autism.