Periconceptional use of the following agent leads to reduced incidence of neural tube defects
Folic acid
Iron
Calcium
Vitamin A
Women should begin taking folic acid supplements before becoming pregnant and continue taking the supplements of at least 0.4 mg/day throughout the first trimester to reduce the risk of neural tube defects. It has been shown to reduce the occurrence and recurrence of neural tube defects . For low-risk women, folic acid supplementation of 400 micrograms per day currently is recommended For women at high risk of NTDs or who have had a previous pregnancy with an NTD, folic acid supplementation of 4 mg per day is recommended.
Intra Uterine Growth Restriction, Intrapaum and Antepaum Fetal Surviellance