Background: b-Thalassemia major is a serious medical problem.Growth retardation is commonly seen in poly-transfused b-thalassemia patients. The exact mechanism of short stature in childrenwith thalassemia major is not well understood, however, it isbelieved to be multi-factorial.Objective: To study the growth state and its relationship to growthhormone (GH) deficiency in b-thalassemia patients.Methods: The extent of growth and growth hormone deficiencywere evaluated in 150 patients aged 10-22 years (84 males, 66 females)residing in Shiraz. The age, sex, height, weight and serumferritin levels were recorded using a questionnaire. Growth hormonesecretion was determined with L-Dopa provocative test in 138 b-thalassemia patients.Results: Short stature was present in 64% of patients (63.6% ofgirls, 69% of boys). Growth hormone deficiency was present in57.5% of 138 patients, (53.5% of boys, 46.5% of girls). Short staturewas found in 83.5% of GH deficient and 74.6% of GH sufficient(p=0.22) subjects. There was no difference between the height ofGH deficient and GH sufficient patients (p=0.297). Age at the startof chelating therapy, height deficiency and serum ferritin levels didnot differ in GH deficient compared to GH sufficient patients.Conclusion: This study suggests that growth retardation and GHdeficiency are common in thalassemic patients and that height deficiencymay not be related to GH reserve with the current testingmethods for measurement of GH reserve.