Aztreonam (monograph) Pregnancy Warnings
Aztreonam has been assigned to pregnancy category B by the FDA. Animal studies have failed to reveal evidence of embryotoxicity, fetotoxicity, or teratogenicity. There are no controlled data from human pregnancy studies. Aztreonam crosses the placenta and enters the fetal circulation. Aztreonam should only be given during pregnancy when need has been clearly established.
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