The harm of extracorporeal ejaculation is mainly reflected in the high failure rate of contraception, is not conducive to the harmony of sexual life, and lead to male diseases and other aspects. The extracorporeal ejaculation is also known as the interruption of sexual intercourse, aborting sexual intercourse, that is, in the course of sexual life when the male reaches sexual climax is about to ejaculate, quickly from the vagina to withdraw the penis, so that the semen shot in the body of the female outside of a kind of sexual behavior, is a kind of traditional contraceptive method. 1. Contraceptive failure rate is high: in the process of sexual life, if there is an ejaculation sensation line in vitro ejaculation, in this case there may be a small part of the sperm has entered the body of the sexual partner. If this time is in the female ovulation, there is a high probability of pregnancy, so this contraceptive method is not reliable, very easy to have an accidental pregnancy. 2. Not conducive to sexual harmony: if in the course of sexual life often take the way of extracorporeal ejaculation, will lead to ejaculation reflex is interrupted, may make both men and women produce tension, anxiety and other emotions. 3. lead to male diseases: prolonged extracorporeal ejaculation, some patients may trigger premature ejaculation and other symptoms, may also appear erectile dysfunction. It is recommended that people with contraceptive needs use scientific and modern contraceptive methods such as condoms for contraception.