Herbal supplements during pregnancy are often viewed as natural and safe options to support maternal health, but their influence on the risk of autism spectrum disorder (ASD) in children is a complex and not fully understood topic. Autism is a neurodevelopmental condition characterized by challenges in communication, social interaction, and behavior, and its causes involve a combination of genetic and environmental factors. Among these environmental factors, maternal nutrition and supplement intake during pregnancy have drawn significant attention for their potential role in shaping neurodevelopmental outcomes.
Pregnant women frequently use herbal supplements to address common pregnancy-related symptoms or to promote overall wellness. These supplements can include a wide range of botanicals such as ginger, chamomile, raspberry leaf, and others. However, unlike prenatal vitamins, which are specifically formulated and studied for pregnancy, many herbal supplements lack rigorous scientific evaluation regarding their safety and effects on fetal brain development.
One of the most studied nutritional factors related to autism risk is folic acid, a synthetic form of folate, a B-vitamin essential for DNA synthesis and neural tube development. Research has consistently shown that adequate folic acid intake before conception and during early pregnancy reduces the risk of neural tube defects and may also lower the risk of autism. This protective effect is thought to arise because folic acid supports critical processes in brain development, including cell division and methylation pathways that regulate gene expression. Prenatal vitamins containing folic acid are widely recommended for this reason.
Vitamin D is another nutrient that has been linked to neurodevelopment. Studies suggest that sufficient maternal vitamin D levels during pregnancy may reduce the likelihood of autism traits in children. Vitamin D influences brain development through its role in immune regulation and neuronal growth. Multivitamin supplements that include vitamin D, along with folic acid, appear to have a beneficial effect on reducing the risk of neurodevelopmental disorders such as autism and ADHD.
In contrast, the impact of herbal supplements on autism risk is less clear and more concerning. Many herbal products have not been studied for their effects on pregnancy or fetal brain development. Some herbs may interfere with the absorption or metabolism of essential nutrients like folic acid, potentially diminishing their protective effects. For example, certain herbal compounds could alter folate receptor function or compete with folate pathways, which might theoretically increase the risk of neurodevelopmental issues.
Moreover, herbal supplements can vary widely in their composition, potency, and purity. Unlike regulated pharmaceuticals or prenatal vitamins, herbal products may contain contaminants or inconsistent levels of active ingredients
