A. Adequate and well-controlled human studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy, and there is no risk in later trimesters.
B. Animal reproduction studies have failed to demonstrate a risk to the fetus, and there are no adequate and well controlled studies in pregnant women or animal studies have shown an adverse effect, but adequate and well controlled studies in pregnant women have failed to demonstrate a risk to the feeders in any trimester.
C. Animal reproduction studies have shown an adverse affect on the fetus, and there are no adequate well controlled studies in humans, the potential benefits may warrant use of the drug in pregnant women despite potential risks.
D. There is positive evidence of human fetal risk based on adverse reaction data from investigational all marketing experience or studies in humans, the potential benefits may want use of the drug in pregnant women despite potential risks.
X. Studies in animals or humans have demonstrated fetal abnormalities and or there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience, and the risks involved in use of the drug in pregnant women clearly out with a potential benefits.