Nicotine and alcohol are legal drugs, which damage not only the health of the consumer, but also the society due to health-economic costs. In pregnancy, the consequences of alcohol consumption and smoking for the unborn life in pregnancy are dramatic. The irreversibly damaging effect of alcohol is proven in each stage of the pregnancy, whereby the phase of the organogenesis is the most sensitive period. Beside a higher incidence for deformations of all organs, the damage of the central nervous system is leading, since mental-intellectual retardation of children after alcohol consumption in pregnancy is proven. Smoking in pregnancy leads likewise to harmful effects, with the intrauterine growth retardation of the fetus being the leading smoking-induced pathology. Smoking- and alcohol-induced damages for the unborn life are irreversible with no therapeutic options. The only therapy is prevention, which means complete cessation of alcohol and smoking in pregnancy.