Function of the open or closed cervix
The cervix is the connection between the vagina and the uterus. There is an external cervix that protrudes into the vagina and an internal cervix that closes the uterus from the inside. Between them lies the cervical canal, where cervical mucus is produced. The cervix and cervical mucus change during the course of a cycle or during pregnancy.
- After menstruation, the cervix is hard and closed. It is easy to feel because it protrudes far into the vagina. There is hardly any cervical mucus. The mucus that is present is thick and lumpy.
- During the fertile period, the cervix slowly opens until a fingertip can fit inside. The cervix is soft and high up. It is almost impossible to reach when palpating. The cervical mucus is thin and abundant. This makes it easier for sperm to travel further into the uterus.
- After ovulation, the cervix closes again and the cervical mucus recedes. The tissue only loosens again shortly before the next menstruation.
- Internal vs. external cervix: The internal cervix is located at the transition to the uterus, while the external cervix is the visible part in the vaginal area. Both change during the cycle, with the internal cervix often softening first.
Opening of the cervix during childbirth
During pregnancy, the cervix is tightly closed. This protects the baby from germs and keeps it stable in the uterus. During prenatal checkups, the doctor regularly checks the degree of opening, length, and consistency of the cervix. In a complication-free pregnancy, the cervix changes a few weeks before birth.
- From the 36th week of pregnancy, the cervix becomes softer and shorter in preparation for birth.
- The mucus plug, which acts as a protective barrier in front of the cervix, comes out. Some women experience increased discharge as a result. However, some women feel the mucus plug coming out in one piece. The discharge may be slightly bloody towards the end. This is called “show.”
- The cervix may open slightly even before the first contractions. However, only regular contractions of the uterus cause the cervix to open slowly and steadily.
- During labor, the midwife will repeatedly check how far the cervix has opened. A cervix measuring 0 cm means it is closed. Once it has reached 10 cm, the birth can begin.
- In addition to the centimeter measurement, professionals assess how easily two fingers can pass through the cervix to gauge progress.
How long it takes for the cervix to dilate
The dilation phase of labor varies from person to person:
- For first-time mothers, dilation can take longer, often several hours to over 10 hours.
- For women who have given birth before, the duration is often shorter because the tissue is already more elastic.
- The speed of dilation depends on factors such as the strength of contractions, cervical elasticity, and the position of the baby.
Cervical insufficiency: Risk of premature birth
Cervical insufficiency can cause premature birth during pregnancy. If you experience increased pain or contractions, a significant increase in discharge, or even bloody discharge, you must see a doctor immediately. Cervical insufficiency has several causes and must be treated accordingly.
- Causes – The increasing pressure of the growing baby can cause the cervix to weaken if there is a genetic weakness in the connective tissue. Premature contractions can be triggered by an infection. They exert strong pressure on the cervix, causing it to open.
- Previous miscarriages, multiple births, or births in quick succession can trigger cervical insufficiency. Malformations or previous operations on the cervix, such as conization or curettage, can contribute to cervical weakness.
- Treatment – Up to the 32nd week of pregnancy, the cervix can be closed with a cerclage. This involves placing a silicone loop or suture around the cervix and pulling it tight, like closing a bag. This stabilizes the cervix.
- The loop is removed again about two weeks before the expected delivery date. At the same time, the expectant mother must remain on bed rest to prevent a threatened premature birth. In most cases, pregnant women are only allowed to get up to go to the toilet. This is to relieve pressure on the cervix.
- If contractions occur at the same time, tocolytics are necessary. These are drugs that inhibit contractions. For such treatment, the expectant mother is usually admitted to hospital.
- Cervical insufficiency has no effect on the baby’s well-being. The longer it remains in the womb, the better it can develop. This can prevent the consequences of premature birth.
