The cervix has a role in controlling the entry of sperm and microorganisms into the pelvis. It is manifested in the following ways. 1. It facilitates sperm penetration during or near ovulation and interferes with its penetration at other times, so conception is possible only during ovulation intercourse. 2. The cervical canal has the ability to protect sperm from adverse environmental influences and engulfment, such as cervicitis, post-operative cervical surgery, and cervical dysplasia, which affects sperm penetration into the uterine cavity. Therefore, if you are infertile and have the above abnormalities, you should do the appropriate treatment. 3. Replenish the energy of sperm. The water, electrolytes and mucin in the cervical mucus can replenish the sperm’s ability to survive for a longer period of time. 4, filtering effect, the cervix out of the closed state during the non-ovulatory period can prevent bacteria and other microorganisms to enter the uterine cavity. 5. To provide a short-term sperm storage pool. Sperm can only survive in the vagina for 0.5-2.5 hours, but in the cervical canal for 48 hours, so the sperm in the cervix can keep releasing to the uterine cavity. 6, start sperm acquisition. The sperm need to go through the process of acquisition to have the ability to fertilize, and this process needs to be completed through the cervix. As mentioned above, the cervix has a very important role in the entry of sperm into the uterine cavity and insemination. The cervical mucus score and the post-coital test can be used to assess whether the cervix is strong enough for sperm to penetrate. A score of less than 10 or a negative post-coital test indicates possible cervical infertility and techniques such as intrauterine insemination may be considered to help conception.