A 4 Year Combination Therapy of Growth Hormone and (GnRH) Agonist in Children With a Short Predicted Height

Inclusion Criteria: * Adult height prediction below -2.5 SD : 151 cm for girls and 164 cm for boys based on the vlaamse groeicurve 2004 (vub.ac.be/groeicurven) * Pubertal: breast development at least M2 for girls and at least 4 ml of testicular volume for boys * Bone age \>10 years but \< 12 years for girls and \> 11 but \< 13 years for boys * Signed informed consent Exclusion Criteria: * Adopted children ( different genetic background, lack of data on birth parameters and parents) * Bone dysplasia or sitting height/ total height \> 2 SDS on standards by Gerver et al (see appendix) * Chronic use of glucocorticoids * Previous growth promoting therapy such as GH, sex steroids, oxandrolone, * Known GH deficiency * Chronic infectious disease * Active rheumatic disease * Previously diagnosed or currently suspected malignancy * Sex steroid therapy * Diabetes mellitus * Renal insufficiency (serum creatinine \> 1.5 mg/dl) * Hepatic disease ( liver test \> 4 fold upper limit of normality) * Current congestive heart failure * Inability to follow the study protocol * Treatment with a non registered drug during the last 30 days before the moment of inclusion.