Growth hormone is released by pituitary gland which is located at the base of the brain. Growth hormone helps your bones and muscles to develop properly. Growth hormone levels naturally rise and fall over time. Too high or too low level can cause health problems such as low muscle density, late puberty, low blood sugar, etc. Growth hormone stimulation test will be ordered when growth hormone deficiency is suspected and only when there are appropriate indicators. Signs of growth hormone deficiency in children include lower-than-average height, slow growth rate, poor muscle development, low blood sugar, and late puberty.