The desire to ejaculate at the very beginning of intercourse may be caused by physiological factors, or it may be premature ejaculation due to excessive sensitivity of the glans or reduced ability to control ejaculation. 1. Physiological factors: If it happens by chance, it is often related to psychological factors. Such as the first time sex, sex life experience is not enough, or long-term separation, a long time to meet again, or recent stress, overworked, etc., may appear too excited and tense emotions. This situation occasionally occurs is physiological, timely adjustment of emotional state, can be improved. 2. glans over-sensitivity: if it happens often, it should be considered as premature ejaculation, which may be caused by the elevated sensitivity of the glans, and the smaller stimulus will make the penis produce a strong reaction, and it is easy to have an ejaculatory impulse. You can apply local anesthetic drugs, such as lidocaine gel to reduce glans hypersensitivity, prolong the sexual life time. 3. Reduced ability to control ejaculation: It may also be due to the lack of 5-hydroxytryptamine, resulting in a lower threshold of excitation in the brain, due to the reduced ability to control ejaculation caused by the central premature ejaculation. It is recommended to take oral 5-hydroxytryptamine reuptake inhibitors, such as dapoxetine and sertraline, under the guidance of a doctor. If the physiological factors are excluded, the patient should consult a doctor in time to clarify the cause of the disease and then follow the doctor’s instructions to carry out the appropriate treatment.