[The evaluation of the risk factors for congenital hypothyroidism: the outlook of a case-control study].

The availability of a National Register of congenital hypothyroid infants allowed to perform descriptive studies on characteristics of the cases and the efficiency of the neonatal screening. Continuous and exhaustive recording of data concerning congenital hypothyroidism cases provided valuable epidemiological informations about congenital hypothyroidism in Italy. Moreover, the National Register allowed to develop a network of collaboration which can promote a population based case-control study. As the etiopathogenesis of congenital hypothyroidism has not been completely elucidated, performing of a case-control study can contribute to evidence the most important risk factors of congenital hypothyroidism and to improve the prevention also by prenatal diagnosis of this disease. Screening centers will be involved in the study and questionnaires of the National Register for congenital hypothyroidism will be used to record case and control informations. A biological bank concerning cases, controls and their parents, will be organized.