INS and diabetes mellitus: (1) Type 1 diabetes (due to autoimmune-cell destruction, usually leading to absolute insulin deficiency, including latent autoimmune diabetes of adulthood), (2) Type 2 diabetes (due to a progressive loss of adequate b-cell insulin secretion frequently on the background of insulin resistance), (3) Specific types of diabetes due to other causes, and (4) Gestational diabetes mellitus (diabetes diagnosed in the second or third trimester of pregnancy that was not overt diabetes prior to gestation).1