TCT is the abbreviation of thin layer liquid-based cytology test, which is a method of cervical cytology diagnosis, generally taking cervical exfoliated cells for cervical cytology test, and analyzing whether the cervix is normal by observing the cell characteristics of cervical exfoliated cells. In 2003, the Department of Disease Control of the Ministry of Health commissioned the China Cancer Research Foundation to organize experts to formulate the Guidelines for Early Diagnosis and Treatment of Cervical Cancer Screening, which recommends that women who have been sexually active for more than 3 years or have sexual intercourse over 21 years old should have cervical cytology examination once a year, and can be re-examined after 3 years if the cytology is normal for 2 consecutive times, so TCT results can only be ensured for 1 year. Sexual intercourse, vaginal medication and vaginal douching are prohibited within 3 days before the TCT examination. TCT should not be performed during menstruation or vaginal bleeding because the blood cells will cover the epithelial cells and lose the significance of the test.