A mother with 10 weeks pregnancy and who had previously delivered a baby with open neural tube defect which statement is true

Ans. is a i.e Sodium valproate causes open neural tube defect Sodium valproate "used during pregnancy, has produced neural tube defects in the offspring; therefore should be avoided". KDT 5/e, p 375 Therefore option "a" is correct "The risk of recurrence of anencephaly is 5% after one affected child and 13% after two affected children deg''