Effect of vitamin D3 supplementation in pregnancy on risk of autism and Attention Deficit Hyperactive Disorder

According to a recent study, maternal preintervention 25(OH)D (maternal 25-hydroxy-vitamin D) when given at a higher dose, decreased the risk of autism, decreased the risk of ADHD diagnosis, and lowered autistic symptom load. The conclusions of this study were published in the American Journal of Clinical Nutrition.

This randomized study was part of the COpenhagen Prospective Study on Neuro-PSYCHiatric Development (COPYCH) project and consisted of 700 healthy mother-child pairs who enrolled at the 24^th week of pregnancy. 25(OH)D was measured at inclusion and 623 mothers underwent randomization to receive either the high-dose of 2800 IU/d (n=315) or standard dose of 400 IU/d (n=308) Vitamin D3 until one week after childbirth. At 10 years of age, diagnoses and symptom load of autism and ADHD, respectively was made utilizing the Kiddie-Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version.

At the end of the study, it was seen from the psychopathologic evaluation that 591 (10-year old) children completed it. Out of this, 16 and 65 children were identified with autism and ADHD, respectively. A total of 496 children participated in the vitamin D3 trial (high-dose: 246; standard-dose: 250), out of which 12 and 58 children were identified with autism and ADHD, respectively.

Based on the above results, it can be concluded that higher levels of maternal preintervention 25(OH)D may be associated with a decreased risk of autism, lower autistic symptom load, and decreased risk of ADHD diagnosis. However, supplementation with high-dose vitamin D3 may not be associated with the risk of autism and ADHD.