Women should take folic acid while they are trying to conceive and during the first three months of pregnancy
Women who take folic acid supplements early in their pregnancy may reduce their child’s risk of autism by 40 per cent, a study found.
But mothers-to-be should start taking them four weeks before conceiving and eight weeks afterwards to get the full benefit for their unborn child.
The timing of taking prenatal supplements is critical, scientists warn.
Folic acid - Vitamin B9 - is required for DNA synthesis and repairs. It’s naturally occurring form, folate, is found in leafy vegetables, peas, lentils, beans, eggs, yeast, and liver.
Folic acid is known to protect against spina bifida and other neural tube defects in children but the latest research, which looks at more than 85,000 babies born in Norway between 2002 and 2008, shows that it may offer protection against Autism Spectrum Disorder (ASD)
Epidemiologist Pel Surin of the Norwegian Institute of Public Health said: 'We examined the rate of autism spectrum disorders in children born to mothers who did or did not take folic acid during pregnancy.
'There was a dramatic reduction in the risk of autistic disorder in children born to mothers who took folic acid supplements.'
Since 1998 the Norwegian health authorities recommended that all women planning to become pregnant take a daily supplement of folic acid from one month before the start of pregnancy.
Scientists looked at the Norwegian Mother and Child Cohort Study and its sub-study of autism, the Autism Birth Cohort Study in which 85,176 babies born between 2002 and 2008 participated.
In the study, published Journal of the American Medical Association, expectant mother’s dietary habits were recorded and families were regularly surveyed for three to 10 years to measure the development of autism spectrum disorders.
A total of 270 cases of autism spectrum disorders were identified in the study population - 114 autistic disorder; 56 Asperger syndrome; and 100 atypical or unspecified autism, otherwise known as pervasive developmental disorder not otherwise specified.
The study found mothers who took folic acid supplements in early pregnancy had a 40 per cent reduced risk of having children with autistic disorder compared with mothers who did not take the supplement.
The reduction in risk for autistic disorder - the most severe form - was observed in those who took folic acid from 4 weeks before to 8 weeks after the start of pregnancy.
No reduction in risk was observed for atypical or unspecified autism while for Asperger syndrome the number of children was too low to obtain sufficient evidence.
The study found the use of folic acid in early pregnancy increased substantially from 2002, 43 per cent, to 2008, 85 per cent, among women who participated in the Norwegian research.
However, many women began taking folic acid later than recommended, and only half started before the beginning of pregnancy
The researchers also analysed whether the risk of autistic disorder was influenced by the use of other dietary supplements, such as cod liver oil and omega-3 fatty acids or vitamins and minerals, but found not link.
In recent years, researchers have started to investigate whether folic acid has other beneficial effects on the development of the foetus’ brain and spinal cord.
A study of language development in the Norwegian cohort published in 2011 showed that children whose mothers took folic acid supplements in early pregnancy had only half the risk of severe language delay at age three years compared with other children.
A separate 2011 study from the University of California demonstrated a lower risk of autism spectrum disorders in children of mothers who had used prenatal vitamin supplements during pregnancy.
Prenatal vitamin supplements contain folic acid in combination with other vitamins and minerals.
Professor of Epidemiology Ezra Susser at Columbia University added: 'Our findings extend earlier work on the significance of folate in brain development and raise the possibility of an important and inexpensive public health intervention for reducing the burden of autism spectrum disorders.'
Read more: http://www.dailymail.co.uk/health/article-2277644/Pregnant-women-folic-acid-reduce-childs-risk-autism-40.html#ixzz2KngLKmtm
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