Erectile dysfunction is not uncommon after radical prostatectomy and men who undergo ADT in addition to this are likely to show further decline in their ability to engage in penetrative intercourse, as well as their desire to do so.  A study looking at the differences of using GnRH-A (and androgen suppressant) or an orchiectomy report differences in sexual interest, the experience of erections, and the prevalence of participating in sexual activity. Men reporting no sexual interest increased from % to % after orchiectomy, and from % to % after GnRH-A; men who experienced no erections increased from % to %; and men who did not report engaging in sexual activity increased from % to % after orchiectomy and % to %.  This study suggests that the GnRH-A and orchiectomy had similar effects on sexual functioning. A vicious cycle whereby lowering testosterone levels leads to decreased sexual activity, which in turn cause both free and total testosterone levels to decline even further.  This demonstrates the importance of androgens for maintaining sexual structures and functions.