Preconceptional evaluation should be extended to all women in reproductive age. It includes, among others, screening for infections, evaluation of immunity against infectious agents detrimental to the fetus and, in high risk cases, detection of genetically transmitted diseases. Furthermore, any medication needs to be evaluated for potential embryotoxicity and teratogenicity. During pregnancy, diseases that may appear trivial in other circumstances can become complex due to the potentially harmful secondary effects of medication and radiodiagnostic tests on the motherand fetus. Knowledge not only of the list of drugs that can be safely used during pregnancy, but also of their special dosages, as well as of the potential risks of radiation of radiologic tests is essential to good clinical management.