I heard that folic acid is useful to be taken before pregnancy is that true? and also vitamins e and c ?!

Yes, folic acid: Folic acid is a great idea if you are trying to conceive, and also during pregnancy. It helps prevent a developmental abnormality in the spine of the fetus. It is not necessary to supplement vitamins E and C during pregnancy, but taking moderate amounts will not hurt. Taking the routine prenatal vitamins is adequate for most women.

Yes and maybe: Adequate Folic Acid helps to prevent neural tube defects, a type of birth defect. Taking any multivitamin will generally give you enough, but check the label on your prenatal vitamins to make sure. Vitamin c is water soluble, and you cannot take too much in any practical sense, because any excess you take will be cleared in your urine. Keep to the rda for vitamin e, however, as it is fat soluble.