A cervical fluid dark zone is usually the presence of fluid in the cervical canal, which is connected to the vagina through the ectocervix. If there is fluid in the cervical canal, it is usually discharged through the ectocervix and does not usually remain in the cervical canal. If a dark area of cervical fluid is found, consider the possibility of cervical effusion, cervical blood accumulation, cervical glandular cysts, etc. 1. Cervical effusion: When the cervical mucosa is damaged, resulting in cervical adhesion, it may cause cervical canal narrowing, and the fluid discharge in the cervical canal will be obstructed and gradually accumulate to form effusion. In this case, the presence of cervical fluid dark area can be observed through imaging, which can be treated by surgical release of adhesions and dilatation of the cervical opening. 2. Cervical blood accumulation: usually occurs after miscarriage, childbirth or menstruation, when there is bleeding, it can be liquid under ultrasound, and if blood accumulates in the cervical canal, a cervical fluid dark area can be observed through imaging, which usually disappears after bleeding stops. If the liquid dark area of the cervix is observed continuously, surgery should be performed in time to remove the accumulated blood. 3. Cervical glandular cyst: When infection occurs in the cervix, it will cause an increase in cervical secretion, which will easily cause cervical blockage or fluid accumulation, which can lead to the inability to discharge the secretion and will also lead to the observation of liquid dark area of the cervix during ultrasound and other examinations. In this case, you can use metronidazole suppositories vaginally or take levofloxacin or roxithromycin orally for treatment. 4. Other cases: If the cervical canal is atrophied and closed in older women, it may also lead to cervical secretions that cannot be discharged and accumulate at the cervix, which may also appear as a dark cervical fluid area during ultrasound examination. Clinically, if there is fluid residue in the cervical canal, there is usually no discomfort, so it is not easy to be detected, and most of the cervical fluid dark areas will gradually disappear after a period of observation, and no treatment is required. If there are uncomfortable symptoms, you should go to the hospital in time to get the appropriate treatment to avoid delaying the disease.