MTHFR and neural tube defect: Folic acid supplementation during pregnancy protects against fetal structural malformations such as NTD and congenital heart problems. According to recent research, it may help protect against premature delivery. The significance of genetic variants in the genes governing folate metabolism (especially the MTHFR gene) and how they impact l-methylfolate bioavailability and, hence, folate supplementation techniques, is not well known