What is the normal length of the cervix?

The cervix is ​​very important for female friends. If some problems occur without paying attention, it will affect the systemic health of female friends and even lead to infertility. Therefore, it must be taken seriously. Moreover, the length of the cervix also has certain standards. Whether it is too long or too short, it will cause considerable trouble and require surgery.

The cervix is ​​located in the lower part of the uterus. It is approximately cone-shaped, 2.5 to 3 cm long, with the upper end connected to the uterine body and the lower end extending deep into the vagina. In layman's terms, as the name suggests, it means the cervix of the uterus, which connects the vagina and the uterus. The specific location is deep in the vagina, adjacent to the uterus.

The position of the external cervical os in the vagina determines the type of uterine displacement. Generally, the normal position of the uterus in an adult woman is slightly anteverted and flexed. "Inclination" refers to the angle between the long axis of the uterine body and the long axis of the vagina; "flexion" refers to the angle between the long axis of the uterine body and the long axis of the cervix. Normal anteversion means that the uterine body and the vagina form an inclination angle that is open forward and approximately right angles; normal anteflexion means that the uterine body and the cervix form a flexion angle of about 170° that is open forward. The external os and lips of the cervix are in contact with the posterior wall of the vagina.

Various physiological or pathological factors may lead to changes in the angle of uterine "tip" and "flexion", resulting in different types of uterine displacement: anterior displacement (anteversion, anteflexion, anteversion-anteflexion), posterior displacement (retroversion, retroflexion, retroversion-retroflexion and horizontal position) and lateral displacement (lateral tilt, lateral flexion, lateral tilt and lateral flexion), etc.

The vault at the top of the vagina divides the cervix into two parts: the part of the cervix that protrudes into the vagina is called the cervicovaginal part, and the part above the vaginal vault is called the upper cervicovaginal part. The center of the cervix is ​​a long, fusiform lumen that is slightly flattened front to back. Its upper end is connected to the uterine cavity through the internal cervical os, and its lower end opens to the vagina through the external cervical os. The cervical canal is between the internal and external openings. The external cervical os is round in nulliparous women and transversely fissured in women who have given birth through vaginal delivery.

The size of the cervix and the ratio of the uterine body vary with age and endocrine status. The cervical wall is composed of the mucosa, muscularis and adventitia.

1. The cervical canal mucosa is the endocervical lining, which is covered by a single layer of columnar epithelium that secretes mucus. The epithelium sinks into adenoid crypts in the lamina propria, which are commonly called cervical glands. They can secrete mucus, which is the main component of leucorrhea.

3. There are reserve cells on the surface of the endocervical canal and below the glandular columnar epithelium and above the basement membrane, which have the potential for bidirectional differentiation: proliferation and differentiation into columnar epithelial cells and metaplasia into squamous epithelium;