In this retrospective study, we review our data on 203 drug-addicted pregnant patients, considering two different aspects of the question: maternal and fetal. We report the findings relative to maternal metabolic, endocrinological, neuroendocrinological and immunological studies performed in our department over the past 13 years. Moreover, we study fetal involvement in drug-addicted pregnancy and report the findings of our fetal behavior and urodynamic studies. The last section of this study deals with perinatal outcome. In particular, we report a high incidence of small-for-gestational-age fetuses and premature deliveries.