How it manifests
Premature ejaculation (ejaculatio praecox) is defined as ejaculation that occurs too soon after the start of sexual intercourse and cannot be voluntarily delayed. In some cases, ejaculation may occur even before penetration.
The answer to the question "how soon is too soon?" depends on the perspective. While relationship therapists sometimes define premature ejaculation as any ejaculation that occurs before the partner reaches sexual satisfaction, the medical definition generally refers to ejaculation occurring within one minute of vaginal penetration.
Ejaculation occurring within one minute is considered premature, while intercourse lasting less than three minutes is generally classified as short-duration intercourse (coitus brevis).
Premature ejaculation may occur in two forms: sthenic and asthenic. Men with the sthenic form usually do not experience erectile dysfunction and are often able to have intercourse repeatedly within a short period of time. In contrast, men with the asthenic form lose their erection immediately after ejaculation despite ongoing sexual arousal. In some cases, ejaculation may even occur without a full erection.