Background: A clear definition of growth response after intervention with therapies such as GH is lacking. The aim of this study is to evaluate growth response to GH therapy and factors affecting it in children with short stature. Patients and methods: the present study was a prospective study that carried on 100 children referred from all-over Upper Egypt to growth clinic at Assiut Health Insurance Clinics, 74 of them were diagnosed as Isolated Growth Hormone Deficiency (IGHD), 6 of them were diagnosed as Multiple Pituitary Hormonal Deficiency (MPHD) and 20 of them were diagnosed as Turner Syndrome. All children had inclusion criteria of age between 4-12 and duration of GH treatment at least one year. Full history taking and physical examination with special concern to the anthropometric measurements initially and follow up every 3 months was recorded. Also records of the children were be reviewed for initial investigations, routine general laboratory tests, which include (complete blood picture, stool examination, complete urine analysis, renal and liver function tests), Thyroid profile free thyroid hormones (FT3, FT4), thyroid stimulating hormone (TSH), growth hormone (GH) secretion by provocation test (insulin tolerance test), Karyotyping when indicated, X-ray of the left wrist and hand, left elbow or shoulder joint for bone age determination. All patients received rhGH with a standard dose of 0.6 IU/kg/week. The calculated dose per week was divided for six days and given subcutaneously at night. Results: There were good response to GH therapy among IGHD cases by increase their height (5-12 cm) during 1st year of treatment. There was highly significant difference in IGHD cases between their height SDs before treatment (-4.94±0.98) and after 1 year of treatment (-4.21±1.03) P-value = 0.0001. Regarding MPHD cases GH therapy lead to a good response by increase their height (7.5-12 cm) during 1st year of treatment. The difference between their height SDs before treatment (-4.94±0.98) and after 1 year of treatment (-4.00±0.48) was close to significant (P-value =0.068). Among Turner syndrome cases GH therapy lead to a good response by increase their height (3.5-8.5 cm) during 1st year of treatment. There is highly significant difference in Turner cases between their height SDs before treatment (-5.74±1.4) and after 1 year of treatment
(-5.33±1.33), P-value=0.0001. There is positive (+ve) correlation coefficient between change in height SD after 1 year of therapy for all study groups and bone age delay
(r= 0.243), target height (r =0.203) and change in height SD after 6 months (r= 0.793).