A :
Adequate, well-controlled studies in pregnant women have not shown an increased risk of fetal abnormalities.
B :
Animal studies have revealed no evidence of harm to the fetus, however, 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 fetus.
C :
Animal studies have shown an adverse effect and there are no adequate and well-controlled studies in pregnant women.
or
No animal studies have been conducted and there are no adequate and well-controlled studies in pregnant women.
D :
Studies, adequate well-controlled or observational, in pregnant women have demonstrated a risk to the fetus. However, the benefits of therapy may outweigh the potential risk.
X :
Studies, adequate well-controlled or observational, in animals or pregnant women have demonstrated positive evidence of fetal abnormalities. Use of the product is contraindicated in women who are or may become pregnant.