Drug use in pregnancy is associated with a number of serious complications for mother and fetus. There are safe data on destructive effects of alcohol, cocain, marijuana and tobacco on pregnancy and neonatal outcome. Of importance is the fact that for many drugs similar effects on pregnancy could be observed: vasoconstriction of the placental vessels resulting in placental abruption, preterm labour (mother), spontaneous abortion, intrauterine growth retardation, low birth weight, preterm delivery and stillbirth (fetus). Symptoms of withdrawal and neurodevelopmental disorders are the most important problems of the neonate. However, only small data exist about the effects of recently popular party drugs like ecstasy or LSD. In addition, from most drugs, with exception of alcohol, safe information about the risk of congenital malformations doesn't exist. Nevertheless they may be a useful guide in the diagnostic of potential malformations by ultrasound. Most of pregnant women using drugs are poly-drug users and are often in reduced general condition. They need therefore the intensive care of the obstetrician in cooperation with other specialists (internal medicine, psychiatry).