Autism spectrum disorder (ASD) is a complex condition, affecting 1 in 68 children. But can it be prevented during pregnancy? Experts weigh in on the latest research.
As soon as the pregnancy test comes back positive, parents will do anything to protect their baby-to-be. That includes doing what they can to lower their child's risk for autism spectrum disorders (ASD), which affect 1 in 68 children. Some research says this can start before birth. One study in the New England Journal of Medicine found differences in the brains of children with autism as early as the second trimester of pregnancy. While researchers haven't been able to pinpoint a definite cause, ASD likely develops from a combination of factors. "Some cases may primarily have a genetic cause, and others may have a primarily environmental cause, but most cases probably result from the interaction of both," says Paul Wang, M.D., senior vice president of medical research for Autism Speaks.
While you can't do much to change genetics, you can alter your exposure to certain environmental factors that have shown a link to ASD. However, none of these lifestyle changes are absolutes—experts can't tell you that lowering your exposure to one particular factor will lower your child's risk. "Evidence about environmental risk during pregnancy is really at its infancy, so any data-supported hypotheses must be investigated further as nothing is yet considered a certain cause," says M. Daniele Fallin, Ph.D., director of the Wendy Klag Center for Autism and Developmental Disabilities at the Johns Hopkins Bloomberg School of Public Health. The key is for pregnant women to take some safe, proactive steps like these that can potentially protect their babies.
Reduce your exposure to air pollution
"Perhaps the most convincing and consistent environmental association with autism risk to date is pregnancy exposure to air pollution," says Dr. Fallin. Multiple studies have shown this connection: One by researchers at the Harvard School of Public Health found that the risk doubled for children born to women exposed to high levels of pollution, particularly in the third trimester. The higher the levels of exposure, the greater the risk. However, that's just part of the story. "The challenge has become understanding what component of air pollution may be relevant, as this implicates hundreds of chemicals from multiple sources," explains Dr. Fallin. In general, the American Lung Association recommends several ways to protect yourself from air pollution: for instance, fill your gas tank up after dark, exercise away from highly-trafficked areas and, when pollution levels are high, take your workout indoors. You can check out your daily air quality levels at www.airnow.gov.
Avoid Toxic Chemicals
There seems to be an increased risk for ASD associated with maternal exposure to certain chemicals during pregnancy, thought a lot more research needs to be done. For instance, one recent study found environmental exposures associated with autism, specifically "traffic-related pollutants, some metals, and several pesticides and phthalates." It can get confusing to figure out exactly which chemicals, such as those found in flame-retardants, plastics, and even cosmetics, to avoid. Talk to your doctor about what's right for you—you might want to limit your intake of canned foods, avoid water bottles made of plastic or aluminum, and stay away from personal care products that list "fragrance" as an ingredient.
Check Your Meds
Researchers have found potential links between the medication a mother takes while pregnant and autism risk. For instance, use of anti-depressants (SSRIs specifically) has shown association with autism across multiple studies, says Dr. Fallin, though it remains unclear whether this link is related specifically to the drugs or to the mother's depression itself. Also, a study in the Journal of the American Medical Association has shown that valproate, a medication used to treat epilepsy and other neurological disorders, can increase the risk for autism. It's crucial that you work with your doctor to determine whether the benefits of any medications you take outweigh the risks. In many cases, they will: "If a mother has epilepsy, it is very important that it be controlled during pregnancy, even if that requires valproate," explains Dr. Wang. "If the mother has a seizure while pregnant, that is potentially a much bigger risk to the fetus than the drug that controls her seizures."
Space Out Your Pregnancies
A study in the Journal of the American Academy of Child & Adolescent Psychiatry found that pregnancies spaced between 2 and 5 years apart have the lowest risk of a child developing autism. Researchers found that those children conceived after less than 12 months were 50 percent more likely to end up with a diagnosis as compared with children conceived between that 2-and-5-year time frame, though it's unclear why.
Meanwhile, those conceived after more than 60 months were 30 percent more likely to be diagnosed. However, keep in mind that autism risk increases with both parents' ages at conception and that a woman's fertility declines as she gets older. When it comes to timing, work with your doctor to determine the best plan for you and your family.
Up Your Folic Acid Intake
Talk to your doctor about taking folic acid supplements. Some studies show that reduced folic acid intake, whether through diet or because of lack of supplementation, may be a risk factor for autism, says Dr. Fallin. The U.S. Department of Health and Human Services recommends pregnant women take between 400 to 800 mcg of folic acid daily.
Take Care of Your Health
Researchers know that maternal health during pregnancy has an impact on the unborn child, and ASD is certainly no exception to this rule. "For instance, women who are severely ill and require hospitalization during pregnancy may be more likely to have children who develop autism," says Dr. Wang. Specifically, studies have shown associations between maternal infections during pregnancy and subsequent risk for their children developing an autism spectrum disorder.
In general, women should do what they can to remain healthy during pregnancy. "This includes optimizing nutrition, taking prenatal vitamins as recommended by their obstetrician, avoiding exposure to unnecessary drugs and medications, and ensuring that their own vaccinations are up to date," says Dr. Wang. Also, a recent study in the Journal of the American Medical Association found that gestational diabetes developed by 26 weeks is linked with an increased risk to ASD. Ask your doctor about the right plan for you and then stick with it.
Give Yourself a Break
Moms are notoriously too hard on themselves, and it's especially important to understand that when it comes to ASD, most of this is out of our control. There's a lot of pressure on pregnant women to make all the right choices, particularly as many worry about their child's potential for developing autism and other disorders, says Dr. Fallin. "For some, this can lead to stress and anxiety, both of which act against promoting good mental health in a pregnant mom," she says. "So, while women should be informed about potential risks during pregnancy, they should remember that no environmental factors have been shown to directly cause autism and can only be considered potential risk factors at the moment. Knowing this information can help shape behavior and policy, but should not be employed to increase maternal anxiety or imply individual blame."