The opening phase is the introductory phase of childbirth. It is characterized by the onset of the first contractions, which open the cervix and cause the amniotic sac to break.
What is the opening phase?
The opening phase is the longest phase of a birth, as it can usually take several hours or even days to dilate the cervix sufficiently. A birth is divided into several phases. Weeks before the birth, the first more or less noticeable sinking contractions begin. These can be improved by applying heat and ensure that the abdomen visibly sinks lower. The baby slides deeper toward the birth canal as a result of these descending, preterm or practice contractions. While these contractions do not affect the cervix and do not induce labor, the first contractions that affect the cervix occur during the opening phase. They tend to be made stronger by heat, which makes them easily distinguishable from preterm contractions. Opening contractions are characteristic of the opening phase and are synonymous with the beginning of labor. During the opening phase, the cervix gradually widens to an opening of about 10 cm so that the baby can be pushed out through the birth canal with the subsequent pushing contractions. As soon as this happens, it is called the expulsion phase. The opening phase is also the longest phase of a birth, as it can usually take several hours or even days to dilate the cervix sufficiently. During the opening phase is the right time to administer pain medication so that the woman is not too debilitated by the opening contractions.
Function and task
The cervix is the site of transition of the vagina to the uterus. During pregnancy, it has kept the baby safely and tightly enclosed in the uterus, not allowing germs or foreign bodies to get to it. Now, however, the baby must be pushed through the vagina into the outside world – and this is only possible if the cervix dilates sufficiently for this purpose. So the main purpose of the opening phase is to gradually open the cervix so that the baby can pass through it. Only then do the much more intense push contractions make sense. During the opening phase, the cervical opening contractions simultaneously ensure that the amniotic sac breaks. Although there are very rare cases in which babies are born with the amniotic sac intact, in most cases the amniotic fluid goes out before this happens. For the accompanying midwives, the purpose of examining the amniotic fluid is to determine if the baby is doing well. Discoloration would indicate that something is wrong and that help is advised. The opening stage is completed when the cervix has dilated to about 10 cm, as the baby can now be pushed into the birth canal.
Diseases and medical conditions
The opening phase is a long-lasting and critical phase, as it prepares for the actual birth. A first possible complication in this process is the so-called precipitous birth, in which the opening phase is unusually fast. In the case of precipitous births, the baby is born in a fraction of the time: the cervix opens faster than expected, and the expulsion phase starts after a very short time. Some fall births happen so quickly that the woman does not make it to the hospital – if she needs medical help, this can be dangerous. However, such rapid births are also commonplace. It is far more common for the cervix to open very slowly or not wide during the opening phase. This is referred to as a birth arrest. The opening contractions usually still come every few minutes, but no longer affect the cervix. At best, gentle help can then be given during the opening phase, for example with labor-promoting drugs; at worst, even these do not help and a cesarean section is necessary. Since the baby will soon have to leave the womb and breathe on its own after the water breaks, there is not too much time left and the cervix must open as quickly as possible. Furthermore, it should be remembered that the contractions of the opening phase already debilitate the mother. They return every few minutes and must be breathed each time, which takes strength. Especially births that drag on for several hours or even days are an immense strain for the mother. In some cases, it happens that the mother is already threatened during the opening phase that she will no longer be able to cope with the pressure contractions.If she cannot push along strongly enough, the expulsion will take all the longer. Therefore, depending on the strength of the contractions and the sensitivity of the woman, doctors like to give pain medication in the form of an epidural during the opening phase, which helps the woman to save her strength for the actual birth of the child. If an epidural is dosed correctly, the woman feels less pain from the contractions, making them easy to endure, and can still feel enough pressure from the pushing contractions during the expulsion phase to push along at the right moment. If she were no longer strong enough to do this due to a difficult, prolonged opening phase of labor, there is a risk of needing a cesarean section to deliver the baby in time.
