The most common of all sexual dysfunctions in men is premature ejaculation. The diagnosis of premature ejaculation is established by patient history. Efforts to distinguish premature ejaculation from erectile dysfunction need to be made. The classic history is that a man with premature ejaculation can get a rigid erection, but loses the erection because of inability to control ejaculation. Men with erectile dysfunction typically have a less rigid erection initially, and lose their erection without ejaculating. Men who have erectile dysfunction from venous leakage, however, can have a relatively rigid erection initially and ejaculate without control before losing the erection due to the erectile dysfunction. Thus, in some cases, it is virtually impossible to distinguish the two sexual dysfunctions, and the assumption is that the patient has both erectile dysfunction and premature ejaculation.
An objective measure that can be used in the diagnosis of premature ejaculation is intravaginal ejaculatory latency time (IELT). This is the time recorded by stopwatch from when a man penetrates to when he ejaculates. On average for sexual intercourse, the IELT is approximately seven minutes, whereas the IELT of a man with premature ejaculation is one to two minutes. There are also validated questionnaires that may be completed for assessment of premature ejaculation.
Normal erectile function test results in a man with symptoms consistent with premature ejaculation will help confirm the premature ejaculation diagnosis.