Early folic acid supplementation may halve the risk of birth defects in women using antiseizure medication

Women taking antiseizure medication for epilepsy have around a 45% reduced risk of major congenital anomalies in their children—if they initiate high-dose folic acid before pregnancy. This is the finding of a large Nordic register-based study (SCAN-AED) involving Aarhus University Hospital. The study also finds that starting folic acid supplementation after pregnancy onset is not associated with any protective effect.