Do mums to be take folic acid only once they find out they're pregnant, or even before they get pregnant?

You should start the moment u find out that you are pregnant. Folic acid reduces the risk for birth defects of a baby's brain and spine -- spina bifida and anencephaly -- by 50% to 70%. Folic acid may also lower the risk of preeclampsia and early labor. You can get 5mg folic acid tablets from any Guardian pharmacy or NTUC Unity pharmacy.