Unable to hold back ejaculation may be due to high sensitivity of the glans, endocrine diseases, mental psychological factors and other reasons. 1. High glans sensitivity: male final ejaculation occurs after the glans is strongly stimulated, if you always can’t hold back ejaculation, it may be because of their own glans sensitivity is too high. For example, the number and distribution of dorsal penile nerves of some people are abnormal, and the excitability is high. 2. Endocrine diseases: such as certain patients suffering from thyroid disease can lead to premature ejaculation, in addition to prolactin, testosterone and other secretion abnormalities, may lead to premature ejaculation, that is, can not hold back ejaculation. 3. mental psychological factors: in the process of sexual life, if the feeling of tension, anxiety and other emotions, or lack of sexual knowledge sexual skills, may also lead to rapid ejaculation. There are many other reasons for not being able to hold back ejaculation, such as organic lesions of the reproductive system, prostatitis, etc., please consult the hospital in time, under the guidance of the doctor active treatment, do not self-medication.