For newly married couples who do not want to have children, they need to choose the right contraceptive method, so which contraceptive methods are undesirable? Here are four undesirable contraceptive methods. 1, intercourse without ejaculation method that men in the process of sexual intercourse, near the orgasm is about to thank semen, suddenly artificial control not to thank semen or immediately terminate intercourse. As we know, men have a small amount of sperm into the female vagina before thanking the sperm, so this method is also very difficult to achieve the effect of contraception. In addition, the long-term use of this method of sexual life, easy to cause men impotence, ejaculation abnormalities (such as ejaculation is not smooth or painful, or even can not ejaculate), frequent ejaculation, induced sterile prostatitis and other diseases. The actual fact is that it is also difficult for the man to get the “right” amount of time. 2, in vitro ejaculation method In vitro ejaculation method refers to sexual intercourse, when the man will have a sense of ejaculation, that is, before ejaculation in time to withdraw the penis from the vagina, the semen ejected outside the vagina, so that the sperm can not meet the egg, so as to achieve the purpose of contraception. It is easy to get pregnant using this method. This is because during sexual intercourse, the man often has a little semen flowing into the vagina along with prostate fluid before ejaculation, or when sexual pleasure reaches its peak, the action of withdrawing the penis is a little slow (“fire” is difficult to grasp accurately), part of the semen has been ejaculated into the vagina, thus leading to contraceptive failure. In addition, this method is easy to make both men and women due to excessive attention to ejaculation time and mental tension, so that the process of sexual intercourse is not complete, and over time may even cause sexual neurasthenia. 3, female sex after urination method vagina and urethra are two different pipes, female vaginal opening is larger, located between the urethra and the anus, urination is not possible to flush sperm out of the vaginal opening and achieve the purpose of contraception. 4, irrigation vaginal method Some couples do not contraception when intercourse, and then after intercourse to irrigate the vagina, thinking that this can contraception. In fact, this method is not safe, because the penis in the vagina after ejaculation, numerous sperm will quickly swim to the uterus, irrigation can not be all the sperm flushed out of the vaginal opening. It is recommended that you choose other safer and more effective methods of contraception.