Teratogenic drugs have been identified: various antitumor drugs: such as nitrogen mustard, cyclophosphamide, etc..　　Hormonal drugs: including glucocorticoids and estrogen.　　Glucose-lowering drugs: such as methylsulfonylurea, chlorosulfopropylurea, hypoglycemia, and so on.　　Sedative and tranquilizing drugs and anesthesia drugs: such as Librium, Valium, reaction stop, etc.　　Antiepileptic drugs: e.g. phenytoin sodium.　　Antithyroid drugs: e.g. thiouracil, itbazole, etc.　　Vitamin drugs: such as vitamin A and D and should not be blindly applied in large quantities during pregnancy.　　Among the commonly used antibiotics, penicillin and cephalosporins are relatively safe and have not yet been reported to cause malformations. Streptomycin, tetracycline, gentamicin, kanamycin, chloramphenicol, quinolone and other drugs have the possibility of teratogenicity, should be used with caution during pregnancy.