Autism Risk: Risk of Autism Rises in Closely Spaced Pregnancies

Autism risk could rise in pregnancies where the children are conceived shortly after the first one is born, according to a new study.

Researchers at Columbia University found the risk of receiving an autism diagnosis tripled in a second-born child if the child was conceived within 12 months of the birth of the first baby.

The study, published in the journal Pediatrics, also says second-born children conceived between 12 and 23 months after a first child was born had twice the risk of autism compared to babies conceived at least three years after the first child.

Researchers scrutinized birth records from 662,730 second-born children from California, all of whom were born between 1992 and 2002 and none of whom had an older sibling with autism. By age 6, 3,137 of the second-borns had received a diagnosis of autism, according to data provided by Californias Department of Developmental Services. Of those, 2,747 occurred in children born less than 36 months after their siblings, the study showed.

The studys lead author, Keely Cheslack-Postava, a post-doctoral researcher at Columbia says the cause could be that shortly after a birth, new mothers are deficient in certain nutrients that are key to a healthy pregnancy.

However, the study cannot conclusively say pregnancy spacing is a cause of autism, Cheslack- Postava said.
At this point we arent able to say from this research that delaying a second pregnancy would have an effect on autism risk, said Cheslack-Postava.

There are a lot of people who have closely spaced pregnancies who dont go on to have children with autism, said Dr. Rita Cantor, a professor of human genetics at the David Geffen School of Medicine at the University of California, Los Angeles.

We havent had too much success in finding environmental factors for autism, Cantor said. And if you consider the in utero environment to be an environmental factor which it is then this is a good first step.

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