Mother’s Iron Level Tied to Child’s Autism Risk

Mothers of children with autism were less likely to report taking iron supplements during pregnancy

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Iron deficiency has been associated with autism in past studies, such as one published in Pediatrics in 2012. And children of mothers who have too little iron during pregnancy may also have a higher risk of getting this condition.

Many women don’t have enough of the iron that their bodies need during the second and third trimesters of pregnancy. A lack of iron can lead to anemia. A person with anemia doesn’t have enough healthy red blood cells giving oxygen to her tissues.

New research found that women 35 and older who were not taking iron supplements before and during pregnancy faced a much higher risk of having children with autism than those who took supplements.

"Check that iron levels are adequate during pregnancy."

In an interview with dailyRx News, Andre Hall, MD, an OB-GYN at Birth and Women's Care, PA in Fayetteville, NC, explained why many women take iron supplements during pregnancy.

"During pregnancy, the total volume of blood increases by about 50 percent, but the percentage blood cell count decreases. As a result, most pregnant women are anemic. Iron supplementation is therefore helpful in addressing this anemia," said Dr. Hall, who was not involved in this study.

"Anemia, when left untreated, increases the stress on many organs, including the heart, which must work harder in order to move more blood through the body in order to get the same amount of oxygen to the tissues," he said.

"Reducing anemia also helps support normal fetal development. Iron is well tolerated by pregnant women, although constipation is a common complaint that is usually managed by increasing water intake and/or the use of a stool softener," he said.

This study was led by Rebecca J. Schmidt, PhD, professor with the MIND Institute at the University of California, Davis.

Dr. Schmidt and team assessed data on 520 pairs of mothers and children who had autism spectrum disorders (ASDs).

ASDs are conditions that appear in early childhood. They are marked by trouble communicating and forming relationships. These disorders can cause major social and behavioral challenges.

The authors noted that ASDs affect 1 in 68 children in the US. This number is likely to keep rising, they wrote.

The authors also reviewed details on 346 mothers and children who had normal development.

The mother-child pairs took part in the Northern California-based Childhood Autism Risks from Genetics and the Environment study between 2002 and 2009.

Dr. Schmidt and colleagues focused on iron intake among the mothers. They noted frequency, dosages and supplement brands. They also looked at how many vitamins, other supplements, and breakfast cereals mothers were getting during the three months prior to giving birth and during breastfeeding.

The authors said low iron intake was associated with a fivefold greater risk of autism in children. The risk applied if the mother was 35 or older at time of birth or if she had obesity, hypertension, diabetes or other metabolic conditions.

Iron is crucial in early brain development. Iron deficiency, and the anemia that can come from it, is a common deficiency that affects 40 to 50 percent of women and their babies, Dr. Schmidt said.

“This study indicates a potential role of maternal iron intake in autism, especially for women of advanced age or with conditions like obesity that can predispose them to iron insufficiency," she told dailyRx News. "Women should be sure to follow their doctor's recommendations on taking iron supplements during pregnancy."

Dr. Schmidt added that breakfast cereals fortified with iron can be a major source of iron, after prenatal vitamins and iron supplements.

“We observed significantly lower iron intake from breakfast cereals for moms of children with autism compared with moms of typically developing children,” she said.

The study was published online Sept. 22 in the American Journal of Epidemiology.

The research was funded by grants from the National Institutes of Health, the Science to Achieve Results program and the UC Davis MIND Institute. The authors disclosed no conflicts of interest.

Review Date: 
September 19, 2014
Last Updated:
September 23, 2014