Effect of obesity on the hypothalamo-pituitary-gonadal function in childhood

In 22 normal and 35 obese boys a gonadal function test (2000 IU of hCG i.m. daily for three days and assays of plasma testosterone before and after the hCG administration) was carried out. All the "short normal" children and 31 obese subjects underwent the LH-RH test (50 microng i.v.). While basal testosterone was similar in the two groups of children, after hCG testosterone was significantly (p less than 0.001) lower in the obese boys, In the normal children a significant positive correlation between bone age and basal and after hCG testosterone was demonstrated; this correlation was not found in the obese boys. The pituitary reserve of gonadotrophins did not show significant differences between the two groups of children. Finally a significant positive correlation (p less than 0.01) between the LH curve area during the LH-RH test and bone age was found only in the normal boys.