Hypothyroidism is deficient functioning of the thyroid gland. Congenital hypothyroidism can lead to cretinism in children. In adults the condition is called myxedema. More common in women, it causes physical and mental slowness, weight gain, sensitivity to cold, , and susceptibility to infection. It can be due to a defect of the gland itself or a lack of iodine, both of which can lead to goiter or to inadequate stimulation of the thyroid gland by the pituitary. It is treated with the hormone thyroxine.