What is the role of cervical mucus examination in the diagnosis of functional uterine bleeding?

Cervical mucus examination is a simple method to detect ovarian function. It is often used to determine whether ovulation occurs and guide the treatment of infertility, assist in the diagnosis of early pregnancy, menstrual disorders, detect the cause of amenorrhea, and the type of dysfunctional uterine bleeding. During the menstrual cycle, the quantity and quality of cervical mucus change periodically. Clinically, observing the changes in cervical mucus has certain application value in guiding menstrual disorders.

The main purpose of this test for functional uterine bleeding is to determine whether the ovaries have ovulation function. Check the cervical mucus before or on the day of bleeding. If fern-like crystals are seen, it is a sign of anovulatory bleeding. During the treatment process, observing the mucus can help choose drugs and determine their dosages. For example, if progesterone drugs are used during functional uterine bleeding and fern-like crystals are still seen, it indicates that the dosage of the drug used is insufficient. When using other measures to promote ovulation function, observing the periodic changes in mucus can also help evaluate the efficacy.

There are four main steps for cervical mucus examination:

(1) Take the lithotomy position, use a speculum to expose the cervix, and observe the transparency and viscosity of the cervical mucus.

(2) Use a sterile cotton ball to wipe away secretions from the cervix and vaginal vault, and use a long flat forceps to extend about 1 cm into the cervical canal to pick up mucus.

(3) Open the long flat forceps, observe the length of the mucus thread, place the mucus on a glass slide, and apply it in one direction.

(4) After the slide is air-dried or baked, observe the crystallization state under a low-power microscope.