Antimicrobials are one of the most usually prescribed medications in modern medicine. Most antimicrobials good crosses placental barrier and is safe for mother and child. However, part of this group of drugs is expressed the so-called adverse teratogenic effects on the fetus and they are barred from use in pregnancy. The term teratogenicity covers a group of phenomena and malformations created in a prenatal developmental stage. Teratogenic effect stands for embryo harming in a moment of organogenesis that is considered to be the most sensitive period of a development. Organ with the highest level of sensitivity during the exposure to teratogenic effect defines the type of malformation. Central nervous system, heart, brain, ears and genital system are most frequently harmed. In this final work was made an overview of the teratogenic effects of the most frequently used antimicrobial drugs. Transplacental transmission and teratogenic effect has been proven for a certain number of antimicrobial drugs which should not be used during pregnancy. The majority of antimicrobial drugs can be used safely during pregnancy without doing any harm to the baby