Iodine deficiency is a major health problem worldwide, including our country. Iodine is an essential micronutrient required for thyroid hormone biosynthesis, and the dietary intake recommended by WHO is 150 ¿g/day for adults, and 250 ¿g/day in pregnant women. A diet poor in iodine causes a reduced production of TH, essential for the normal functioning of all the organs of our body. The reduced TH synthesis may cause different pathological conditions, known as Iodine Deficiency Disorders (IDD), depending on the period of life in which it occurs. In Italy a law was issued in 2005 which made it mandatory, in all commercial points, the sale of only iodized salt (30 mg/Kg salt), with non-iodized salt available only on specific consumer request. This measure, together with public awareness campaigns, should lead to a drastic reduction of IDD. In order to verify the effectiveness of this national iodoprophylaxis program, a center for the monitoring the national iodoprophylaxis program (OSNAMI ¿ Osservatorio Nazionale per il Monitoraggio della Iodoprofilassi in Italia) has been set up at the ¿Istituto Superiore di Sanità¿ which monitor the results of the investigations carried out by the individual regional Observatories, including the Observatory of Lazio of which Prof. Salvatore Ulisse is responsible. Previous studies, performed in the south Lazio as well in the city of Rome, evidenced as pregnant women of these areas are characterized by an insufficient iodine intake with increased goiter prevalence. In this context, aim of the present study is to evaluate iodine intake in pregnant women of Rieti and Viterbo in northern Lazio. To this end, in collaboration with gynecological and Obstetric Units of the Rieti and Viterbo hospitals, pregnant and control non-pregnant women will be enrolled in the study to evaluate iodine intake, goiter volume and TH serum levels. The results of the study will be share with the OSNAMI in order to evaluate them in a national context.