Back-to-Back Pregnancies May Increase Autism Risk
Researchers Say Closely Timed Pregnancies May Deplete Mothers of Key Nutrients, Such as Folate
Autism Community Reacts
The new findings are “significant and intriguing,” says Andy Shih, PhD, vice president of scientific affairs at Autism Speaks. “It is not a simple picture."
“There has been a lot of attention on environmental postnatal factors of autism, but this study suggests that when you have children too closely together, you may not be providing an optimal womb environment,” Shih says.
Other studies have shown that pregnancy complications, low-birth-weight babies, and premature births may also be associated with increased risk for autism, he says.
“The real exciting aspect is the focus on prenatal risk factors, and it points to venues of new research to identify what is happening in shorter IPIs as opposed to longer ones,” he says. “We need a lot more follow-up to make sure we are seeing something that is robust and real."
“If you are worried or concerned, work with your obstetrician/gynecologist on your childbirth and reproductive strategy,” he says. “As time progresses, we’ll soon know if this is something to think about in regard to family planning.”
Dan Khoury, MD, chief of the section of developmental and behavioral pediatrics at Nationwide Children’s Hospital in Columbus, Ohio, urges people to keep the new findings in perspective.
The absolute risk of autism, 1%, is still on the low side, he says.
“Closely spaced pregnancies increase the risk of autism, and that is really all we can say now,” he says.
“Pregnancy is very taxing on the mother and depletes a variety of nutritional stores, including iron and folate, so one theory is some deficiency of nutritional stores is at play, and if, in fact, that is what is causing this increased risk, we think we may be able to treat it through supplementation,” he says.
Fred R. Volkmar, MD, the Irving B. Harris Professor and director at the Child Study Center at Yale University in New Haven, agrees that the findings need replication before any conclusions can be drawn.
“This is preliminary, and nobody else has seen this yet,” he says. “We don’t know if it is true, or if it is true, why would it be true.”
Autism risk aside, many challenges exist for parents who have children so close in age, he says.
“The party line used to be to wait three years between pregnancies, and that is still not bad advice,” he says.
“It is too early to make a recommendation, but be aware of this,” says Gary Goldstein, MD, president and CEO of the Kennedy Krieger Institute in Baltimore. “The data is striking, and I was really taken by this study, but this is a new thought."