Drogas y teratogenia

The problem of the malformed children has concerned the humanity for ever, and this also includes the prenatal exposure to drugs of abuse. Tobacco and alcohol are the most common legal drugs used in pregnancy, and cannabis and cocaine, the most common illegal drugs. The use of drugs has been associated with a wide range of structural malformations, but with the exception of the alcohol and the fetal alcohol syndrome, drugs of abuse seem to have a weak teratogenic potential, in the classical structural malformation conception. Nevertheless, there has been found association between the prenatal exposure to these drugs and specific behavioural alterations, usually very subtle but that should not be ignored. This kind of alterations are now included in the conception of teratogenesis. So, drug use during pregnancy is a risk factor, usually associated to other concomitant risk factors like nutrition deficits, maternal illness and poverty, and these effects are overlapped, potentiated and very often confounded. In this review the main variables involved in the development of teratogenesis (factors that should be take into account in a specific exposition to evaluate the potential risk, the roll of the placenta, etc) are analysed. The epidemiology of the drug abuse in pregnancy and the concomitant factors that make difficult this evaluation are also studied. Finally a review of the main teratogenic effects related to the most common abused drugs was done.