PDE5A and erectile dysfunction: Similar evidence was not identified in femalepatients, consistent with the notion that any effects of PDE5 inhibition on fertility inmale patients may be attributable to penile mechanisms.29, 30, 31, 32 Erectile function is reduced in malepatients with infertility, and it is estimated that more than one third of the malepartners in couples seeking fertility treatment experience erectile dysfunction.33, 34 However, extra-penile mechanisms may also beat play.