Impaired growth hormone secretion and increased growth hormone-binding protein levels in subfertile males

To evaluate GH secretion in subfertile males. Comparing GH secretion to a GH stimulation test in two different patient groups and in a control group. Nine Oligozoospermic patients, nine asthenozoospermic patients, and nine age- and body mass index-matched fertile males with normal spermograms. All subjects underwent an IV arginine GH stimulation test. Serum levels of FSH, LH, PRL, E2, T, insulin-like growth factor I (IGF-I), and GH-binding protein were measured. Basal levels of GH were similar in all three groups and serum GH increased in all groups after arginine. However, there was a significant difference between the two patient groups and the control group characterized by an impaired GH response in the subfertile patients. Serum FSH and serum GH-binding protein were significantly higher in the patient groups compared with the controls. Serum LH, PRL, T, E2, and IGF-I were similar in all three groups. This study demonstrates that subfertile men may suffer from relative GH insufficiency, which could have therapeutical implications.