[Frequency of consanguineous unions in the Tlemcen area (West Algeria)].

In order to describe consanguineous unions and their effects in a sample of the Algerian population, we interviewed 3,983 couples in a hospital and from urban and rural areas near Tlemcen. We observed that unions between cousins represented 34.0% of the marriages. The frequency of unions between relatives was lower in the urban (30.6%) than in the rural areas (40.5%). This difference can be explained by changing custom and family relationships in urban areas, and is evidenced by social and anthropologic factors and the attitude towards consanguineous unions.