Growth retardation resulting in abnormally short adult stature. It is caused by a variety of hereditary and metabolic disorders. Pituitary dwarfism is caused by insufficient growth hormone. Hereditary dwarfisms include achondroplasia, with normal trunk size but short limbs and a large head; hypochondroplasia, similar except for normal head size; and diastrophic dwarfism, with progressive, crippling skeletal deformities. Intelligence is normal in these forms of dwarfism. Some kinds include intellectual disability. Dwarfism may also result from inadequate nutrition in early life (seerickets).