The cervix: a connection from the inside out

The womb consists of the uterus and the cervix, which is around four centimetres in length. It is shaped like a slender, upside-down pear. Inside the womb is the uterine cavity, where the foetus grows during pregnancy. The cervix is the connection between the vagina and the uterus. The part that can be seen and felt through the vagina is called the mouth of the uterus. Menstrual blood also flows out of the body through this small opening.

The cervix's protective function

The tissue between the outer mouth of the uterus and the cervical canal is flexible. The vaginal membranes can move into the cervical canal and the mucous membranes from the cervical canal can move towards the cervix, thus increasing the likelihood of infection. Infections can be triggered, for example, by human papillomaviruses (HPV) which can cause cancer. The cervix secretes a special mucous to protect the junction between the vagina and the inner part of the uterus. This makes it difficult for germs to penetrate the body. Its consistency changes during the menstrual cycle.

The fertile phase

The mucous is more liquid around the time of ovulation, i.e., during the fertile phase, and also has a higher pH value. This enables sperm to reach the egg cell. The cervical canal and mouth of the uterus open just a few millimetres. Sperm can survive several days in this environment. Following ovulation, the secretions return to their previous viscous state and the pH value drops.

Changes during pregnancy

The closed cervix protects the unborn baby during pregnancy. The womb expands as the baby grows. Towards the end of pregnancy, the cervix becomes shorter and wider. During labour, the mouth of the uterus opens to allow the child to be born.

The menopause

The cervix changes following the menopause. The opening becomes narrower and produces less mucous. The vaginal membranes also become thinner, making it easier for germs to penetrate.

We recommend annual cervical cancer screening to prevent harmful infections and cancer. The most important examination is the PAP test which enables cell changes to be detected. An HPV test can also be performed if the findings are unclear or abnormal.

Berufsverband der Frauenärzte e.V. (BVF): Innere Genitalien der Frau, 26.03.2018. Frauenärzte im Netz. URL: https://www.frauenaerzte-im-netz.de/koerper-sexualitaet/weibliche-geschlechtsorgane/innere-genitalien/ (abgerufen am: 04.08.2020).

Deutsche Krebsgesellschaft e. V. (DKG): Gebärmutterhalskrebs - Anatomie und Funktion, 14.05.2018. ONKO Internetportal. URL: https://www.krebsgesellschaft.de/onko-internetportal/basis-informationen-krebs/krebsarten/andere-krebsarten/gebaermutterhalskrebs/anatomie-und-funktion/articles/onko-internetportal-basis-informationen-krebs-krebsarten-andere-krebsarten-gebaermutterhalskrebs-anatomie-und-funktion.html (abgerufen am: 03.08.2020).