[Table/Fig-2]:

FDA categories: Teratogenic risks of drugs

Category	Risk factors
A	Controlled studies showed no risk to the fetus.This group is limited to multivitamins and prenatal vitamins.
B	Either animal studies have shown no fetal risk,but there are no controlled human studies during pregnancy ,or animal studies have shown adverse effect that was not confirmed in controlled studies during the first trimester.pencillins are in this family.
C	There are no adequate studies or animal studies have shown adverse effects,but controlled studies in women are not available .Potential benefit must be greater than the risk to the fetus if these medications are used.
D	Evidence of fetal risk is proven,but potential benefit must be thought to outweigh the risks
x	Proven fetal risks clearly outweighs any potential benefits