Cervical mucus is the main component of leucorrhea, a colorless, transparent or yellowish glycoprotein gel secreted by cervical mucous membrane gland cells, which can form mucus plugs attached to the cervix and play a protective role. Before ovulation, under the influence of estrogen, cervical mucus secretion increases, becomes thin and elastic, and can be easily pulled into silk; after ovulation, under the influence of progesterone, cervical mucus secretion decreases and becomes sticky in nature. Therefore, it is a normal physiological phenomenon that the amount of cervical mucus is small, thick and cloudy after the end of menstruation and increases, becomes thin and transparent near the time of ovulation. If the cervical mucus is abnormal, it may be related to abnormal estrogen and progesterone, cervical diseases, etc. 1. abnormal estrogen and progesterone: it is related to endocrine disorders and the use of estrogen and progesterone drugs, which may cause the cervical mucus to be thick and drawn. 2. cervical diseases: acute cervicitis may cause increased cervical mucus, which is often purulent or even purulent, while chronic cervicitis may cause increased cervical mucus, contact hemorrhage, etc.; cervical cancer may cause increased cervical mucus, contact hemorrhage, etc. Cervical cancer often presents thin, bloody cervical mucus; cervical glandular dysplasia or cervical injury, such as partial cervical excision and curettage, can cause a decrease in cervical mucus. In addition to the above, cervical mucus abnormalities also include the presence of anti-sperm antibodies in the cervical mucus. Although this does not affect the nature and discharge of cervical mucus, when sperm come into contact with the cervix, the antibodies bind with the sperm, resulting in the death of the sperm, preventing normal conception and infertility.