Category A
|
Adequate studies in
pregnant women have failed to show a risk to the fetus in
the first trimester and there is no evidence of risk in
later trimesters. |
Category B
|
Animal studies have
failed to show a risk to the fetus but there are no
adequate studies in pregnant women: or animal studies
have shown an adverse effect but human studies have not
shown a risk to the fetus in the first trimester and
there is no evidence of risk in later trimesters. |
Category C
|
Animal studies have shown an adverse
effect on the fetus but there are no adequate studies in
humans, but the benefits may outweigh the risks; or there
are no aminal studies and no adequate human studies. |
Category D
|
Positive evidence of human fetal risk but
the benefits may outweigh the risks. |
Category X
|
Animal or human studies have shown fetal
abnormalities or toxicity, and the risk outweighs the
benefits. |
