15 June 2010
Autism risk tripled with IVF
by Kate Melville
IVF and other assisted fertility treatments may be solving one problem by creating another, suggests a researcher from Tel Aviv University who found a strong link between IVF and mild to moderate cases of autism. IVF has been in the spotlight recently with another study linking assisted reproduction technologies, such as IVF, to congenital malformations.
Dr. Ditza Zachor says her new research at the Assaf Harofeh Autism Center found 10.5 percent of children diagnosed with a disorder on the autism spectrum were conceived using IVF, a significantly higher number than the 3.5 percent autism rate in the general Israeli population.
Zachor is reluctant to draw any definitive conclusions, but she believes the finding poses some urgent questions. "It's too early to make a serious deduction based on that evidence alone," she says, citing other birth-related factors in her study, such as low birth rate and prematurity. Zachor now plans to separate out these risk factors to come up with more precise numbers for autism in IVF.
Zachor speculates that the key may be "imprinting," a biochemical procedure during cell division which determines which genes will be selected or "expressed" in the embryo. Research into epigenetics - changes in gene expression that occur without a change in the DNA sequence - suggest that the malformations may be caused by imprinting abnormalities introduced into the embryo while it's in a test tube environment.
"Many infertile couples choose this procedure [IVF], and they need to know whether there is a risk of autism," concludes Zachor. "However, most women who undergo fertility treatments should not be scared away from IVF procedures: the majority of children born using IVF do not have autism."
Source: Tel Aviv University