Final answer:
Cretinism, primarily caused by Congenital Hypothyroidism due to maternal iodine deficiency during pregnancy, results in severe developmental impairments. Iodine fortification programs, like iodized salt, prevent these conditions in regions where they are implemented.
Step-by-step explanation:
The primary cause of cretinism worldwide due to a lack of dietary iodine during pregnancy is Congenital Hypothyroidism. Cretinism is a condition that arises in children who are born to mothers with severe iodine deficiency. This deficiency disrupts the production of thyroid hormones, T3 and T4, which are critical for brain development and growth. When these hormones cannot be produced during fetal development and early childhood, it can lead to cognitive deficits, stunted growth, hearing loss, and in some cases, speech impairment.
Efforts to prevent such conditions include fortification of salt with iodine, which has helped eliminate iodine deficiency in places where salt consumption is sufficiently high, such as the United States. In regions where iodized salt is not readily available, iodine deficiency remains a significant cause of preventable intellectual disabilities worldwide.