Masters and Johnson have stated that a man ejaculates prematurely if he does so before his partner achieves orgasm in more than fifty percent of his sexual encounters. Other sex researchers consider an early ejaculation the one occurring within two minutes of penetration, though there are some discrepancies about this . Premature Ejaculation in American males is estimated to range from 30-70%.
Most men have experienced the problem of premature ejaculation at some time in their life. Premature ejaculation is one of the most common sexual problems. Premature ejaculation is explained as a condition where in a person is unable to delay ejaculation to a point when it is mutually satisfying for both the partners. That means ejaculation occurs before a man wants it to happen. Some men ejaculate during foreplay while some do so at the very entry itself.
But few men feel that 5 or 10 minutes time to have orgasm is not enough and they feel that this is also premature ejaculation. This suggests premature ejaculation is most likely psychological in origin than physiological. The exact cause of premature ejaculation is still unknown.