Manipulation of the Intratesticular Hormonal Milieu With Exogenous Testosterone (HOP 5) Testicular Aspiration Addendum

The goal of our contraception study (ACY-5) is to develop a hormonal regimen where in all individuals enrolled achieve azoospermia (zero sperm). However, early data demonstrated that some individuals have persistent sperm in their semen despite treatment. We hope to be able to determine whether differences in intratesticular hormone levels account for persistent sperm production in men who do not reach counts of zero as compared to those who do in the male contraceptive study. This study will measure testosterone levels in the testes of men who are participating in male contraceptive studies. Testosterone will be measured in a small amount of testicular fluid at the end of the study treatment phase after sperm counts have been reduced to zero or very low levels.