A lady has history of previous child birth with neural tube defect. What is the dose of folic acid to be given to prevent to neural tube defect in this child: (A) 4000 mcg in periconceptional period, (B) 400 mg after confirmation of pregnancy, (C) 400 mg in periconceptional period, (D) 4000 mcg in 1st / 2nd trimester.
Answer is A. Dose of folic acid for primary prevention is 400 mcg / day
Dose of folic acid for secondary prevention (prevoius child affected with neural tube defect) is 4000 mcg / day started in periconception period = 1 month before to 3 months after conception.