[Premature delivery: epidemiology, etiologic factors, prevention strategies].

Early delivery is not rare, it is an important cause of perinatal mortality. In this study its rate, was 4.95%. The early and late ages of procreation were particularly interested (7.95%) and 3.90%. The first and last parities were more exposed (7.75%-5.31%). The woman occupation was as an important risk-factor. The incidences increased in the poor and rich women groups (7.34%-3.84%) the early labor risk was reduced when the women had efficient prenatal care; when the women had delivered early, the early labor risk increased. So when the women had delivered a stillborn. The early labor risk factor was more important. Finally the authors founded 83.33% of maternal causes could be controlled by efficient prenatal care. Even this rate was so important in the foetal group causes.