Pituitary function in Down's syndrome.

Pituitary function studies have been carried out in eight male and eight female patients with Down's syndrome who were suspected of having hypothyroidism secondary to pituitary deficiency. In all cases, the response of Human Growth Hormone to hypoglycaemia was adequate and the response of Lutenising Hormone and Follicle Stimulating Hormone to the injection of Lutenising Hormone and Follicle Stimulating Hormone was not signfiicantly greater than that in age and sex-matched institutionalised controls. Therefore there is no evidence that the relative hypothyroidism in these patients is due to pituitary hypofunction, nor do the results provide evidence of pituitary deficiency in Down's syndrome generally.