What hormone stimulates spermatogenesis?

Here are some... It's hard to say which one stimulates which; oftentimes multiple factors are interacting to make a organ properly although one of the involved factors may play a major role for its overall functions. For sperm formation, FSH (follicule-stimulating hormone) is the key one but conjunction with healthy testicular tissue and LH as well as testosterone. More? Ask your Dr., preferably urologist.