Efforts to create a hormonal contraceptive for men use testosterone to supp
ress the production of pituitary gonadotropins and hence, spermatogenesis.
However, conventional testosterone must be administered by frequent injecti
on, and, when given alone, is not 100% effective. Therefore, newer androgen
s and agents that synergistically suppress gonadotropin production are bein
g studied to create an effective and commercially viable contraceptive.