GNRH1 and cartilage-hair hypoplasia: The testosterone response to long-term hCG stimulation and peak serum FSH response to GnRH were found to be significantly different in CHH patients (22), but there are potential long-term drawbacks to long-term hCG therapy in males who are FSH-naïve, in terms of promoting differentiation of a limited pool of Sertoli and germ cells before they have a chance to proliferate under FSH stimulation.