Premature ejaculation is a common sexual dysfunction in men, with a prevalence of about 35%-50% in adult men. In the past, the diagnostic criteria were based on the latency of ejaculation (time from penetration to ejaculation) and the number of strokes, such as latency of less than 2 min or less than 10 strokes, or whether the woman reached orgasm. This definition often shows great limitations in clinical application, because premature ejaculation is generally caused by psychological reasons, and almost every man has experienced premature ejaculation, which occasionally occurs on some specific occasions as a normal phenomenon. The causes of premature ejaculation and classification The causes of premature ejaculation are many, and can be one of the factors, or can be caused by a combination of factors. The main factors are: 1, psychological factors: such as sexual impulse is too strong, too long expectation of sexual intercourse, improper choice of sexual object, no quiet and comfortable place for sexual intercourse, lack of security during sexual intercourse and extreme tension, guilt, lack of self-confidence, etc. may lead to premature ejaculation. 2, organic factors: due to the penile sensory nerve sensitivity and excitability is too high, ejaculation threshold is reduced, ejaculation center on penile sensory control dysfunction, etc. 3, other disease factors: circumcision, glansitis, prostatitis, vesiculitis, urethritis, etc. According to the cause and onset, premature ejaculation can be divided into four categories: 1, primary premature ejaculation (lifelong PE): primary premature ejaculation is rare and difficult to diagnose, characterized by the first sexual intercourse; there is no selectivity for sexual partners; premature ejaculation occurs at every sexual intercourse. 2. Acquired premature ejaculation (acquired PE): Acquired premature ejaculation is acquired premature ejaculation with a clear physical or psychological disease etiology. The characteristics are: premature ejaculation occurs at a definite time; the ejaculation time is normal before premature ejaculation occurs; it can occur gradually or suddenly; it can be secondary to urological diseases, thyroid diseases or psychological diseases. 3.Ejaculatory latency instability premature ejaculation (nature variable PE): the ejaculatory latency instability premature ejaculation has a long or short ejaculation time, premature ejaculation occurs from time to time, characterized by: premature ejaculation does not occur continuously, the occurrence time is not regular; when it is about to ejaculate, the ability to control ejaculation is reduced. 4. psychological pseudo-premature ejaculation (premuture-like ejaculatory dysfunction): Patients with psychological pseudo-premature ejaculation often have a normal ejaculatory latency time of 3-6 min, and some even reach 20 min. this type of premature ejaculation is often subjective to the patient and cannot be considered a real pathological process, usually hiding a psychological disorder or a relationship problem with the sexual partner. Characteristics are: subjective belief that ejaculation is too fast; anxiety over subjective belief of premature ejaculation; normal or even long ejaculatory latency for actual vaginal insertion; reduced ability to control ejaculation when ejaculation is about to occur; and anxiety that cannot be explained by other psychiatric disorders.