Fertility Drugs and IVF Linked to Autism
Jun 19, 2010 Joanna Karpasea-Jones
Scientists at the Harvard School of Public Health found that children born to mothers who had taken fertility drugs were nearly 50% more likely to have autism than children naturally conceived.
Researchers asked 111 women who had children diagnosed with autistic spectrum disorder about their medical history and whether they had taken any fertility drugs prior to getting pregnant. Thirty four percent of mothers interviewed had previously taken fertility drugs and a further 24% whose children did not have autism. The drugs in question are those used to induce ovulation, such as Clomid.
History of Infertility Associated with an Increased Risk of Autism
Forty seven percent of mothers of autistic children reported infertility. Other research has suggested that older women have a greater risk of having a child with autism and this ties in with the infertility issue as older women are also more likely to experience infertility or delay in getting pregnant. In the study, the average age at which a mother gave birth to her first child was 35, whereas in the general US population it is 25.
Kristen Lyall, lead author of the study, said “We found that a history of infertility and use of ovulation-inducing drugs was significantly associated with an increased risk of having a child with an autism spectrum disorder.”
Premature Babies Have More Autism
Premature babies are also more likely to suffer from autism and there are statistically more babies born prematurely after IVF than after a natural conception. Premature babies are exposed to many different medications during their treatment in the neonatal intensive care unit, which could be one of the reasons why they develop autism at a greater rate than term babies. They also receive their childhood vaccinations at the same age as other children, rather than their adjusted age, and they have no blood/brain barrier and an underdeveloped immune system so the effects of all these multiple drugs are not known and could certainly be implicated in the higher rate of autism.
In addition, breastfeeding tends to cease early or not begin at all in premature babies who may be too ill to suckle or in hospitals that do not have a supportive breastfeeding policy. Lack of human milk for human babies is known to have a negative neurological effect.
Even after other factors were taken into consideration, IVF and fertility drugs were still found to be significantly implicated in autism.
Younger women having IVF did not have as great a risk of having a child with ASDs as an older woman did.
Another study done in Israel appeared to reach similar conclusions.
Source:
Kristen Lyall, Harvard School of Public Health, Cambridge, Mass.; Andrew Zimmerman, M.D., Kennedy Krieger Institute's Center for Autism and Related Disorders, Baltimore; Ditza Zachor M.D., Autism Center, Assaf Harofeh Medical Center, Tel Aviv University, Israel; presentations, International Meeting for Autism Research, May 20, 2010, Philadelphia.
