A Study of Recombinant Human Growth Hormone Injection for Short Children With Small for Small for Gestational Age(SGA)

Inclusion Criteria: * Clinical diagnosis of full-term small for gestational age, SGA. * Chronological age between 2-6.5 years in girls and 2-7.5 years in boys. Both genders. * Prepubertal stage (Tanner I). * Height was lower than the mean -2SD of the values of normal children of the same age and gender when participating in the study. * A GH peak concentration \>10µg/L in a provocative test within a year before participating in the study. * Bone age\<Chronological age+1. * Normal glucose regulation：Fasting blood-glucose \< 5.6mmol/L, and 2 hours postprandial blood-glucose \< 7.8mmol/L. * Gestational age was 37 to 42 weeks. * The subjects and their guardians signed informed consent. Exclusion Criteria: * Subjects with Liver and renal insufficiency (ALT \> 1.5 times of upper limit of normal value, Cr\> upper limit of normal value). * Patients are positive for antibodies to hepatitis B core (HBc), hepatitis B surface antigen (HBsAg) or hepatitis B e antigen (HBeAg). * Known Highly allergic constitution or allergic to the test drug. * Subjects with diabetes, severe cardiopulmonary and pulmonary disease, and hematological diseases, malignant tumors, or systemic infection, immunocompromised patients and patients with psychosis. * Subjects with other growth disorders, such as Turner syndrome, constitutional delay of growth and puberty, and Laron syndrome and growth hormone receptor deficiency. * Subjects who have received the treatment of GH. * Subjects took part in other clinical trial study within 3 months. * Children who have treated with other hormone (such as gonadal hormone and glucocorticoids etc, continuous administration of more than a month) and that may affect growth hormone secretion or action including oxygen male dragon, growth hormone releasing hormone, etc. within 3 months. * Other conditions which in the opinion of the investigator preclude enrollment into the study.