The, somewhat insensitively called, expulsion phase is the last phase of birth. The baby is forced out of the uterus through the birth canal into the outside world by strong pushing contractions, which is followed by the afterbirth – after which the birth is over.
What is the expulsion phase?
The expulsion phase is the last phase of birth. A human birth is divided into several phases. They all serve to prepare the body for the most intense phase, the expulsion phase. While the descending contractions before the birth made the baby descend as close as possible to the birth canal, the opening contractions served to dilate the cervix. By this time, the amniotic sac has usually also broken, so the baby must now be brought into the world to breathe on its own. The opening contractions came every few minutes and were usually well tolerable in their intensity or were made bearable by the administration of an epidural. The pushing contractions, on the other hand, are characteristic of the expulsion phase, which involves pushing the baby out through the dilated cervix. They are much stronger and more painful and also start every few minutes, but with significant pauses in between. The expulsion phase can last anywhere from a few minutes to an hour or longer, depending on the woman and how labor has progressed so far. While the woman should not push during the opening contractions, she may and must support the pushing contractions of the expulsion phase with strong downward pushing to speed up the process. The pushing contractions end almost immediately after the baby is born. Meanwhile, the placenta usually detaches on its own and leaves the mother’s body through gentler afterthrusts, which usually no longer causes her pain.
Function and task
The expulsion phase is the last phase of a birth. It is followed only by the physical processes after the baby is born. During one of the previous stages of birth, the amniotic sac has broken – if it hasn’t, it will do so now at the latest. The baby is thus no longer surrounded by fluid and must begin to breathe on its own. If it takes too long to get air, there is a risk of suffocation, which is why obstetricians have to intervene in births that take too long. In a normal expulsion phase, the pushing contractions begin, which are much more intense than the previous opening contractions, but many women also find them relieving. The mother’s task now is to assume a position that is suitable for her and to push down hard, thereby supporting the expulsion phase. If she had done this previously during the opening phase of labor, this could have pushed the baby into the birth canal too early. The expulsion phase, however, has exactly this goal. If the birth position is correct, the baby’s head first comes out through the vagina as a result of the pushing contractions, and from then on it usually only takes one or two more contractions for the baby to leave the mother’s body. It can now breathe on its own and starts to cry, which is a sign that its breathing has started to work. Postpartum occurs without contractions; the contractions of the uterus are hormonal and are rarely felt as painful. The placenta usually detaches on its own starting from the center and leaves the woman’s body following the baby. This process usually occurs 10 to 20 minutes after birth.
Diseases and ailments
During the expulsion phase, complications may arise during the delivery of the baby as well as during the postpartum period. If the opening phase was already exhausting, the woman may not have sufficient energy reserves to push along. If the baby cannot be delivered, a cesarean section will be necessary. Before the opening to expulsion phase, the baby should turn again – if this does not happen, the cesarean section is also necessary. At best, the baby only gets stuck awkwardly in the birth canal and an intervention with a suction cup is enough. Difficulties in the expulsion phase can still arise due to the afterbirth. If the placenta does not detach or does not detach completely, it can be helped by external grasping techniques. However, this is only undertaken if the obstetricians are certain that the afterbirth will not detach on its own. The most serious complication is excessive bleeding, in which the mother loses more than 500 ml of blood.These can be stanched by administration of oxytocin and triggered uterine contractions or surgical interventions. Furthermore, it must be examined whether the afterbirth has completely departed after the expulsion phase. If not, the remaining tissue would die and lead to puerperal fever, one of the most common causes of death after childbirth in earlier centuries. Today, this complication is countered with ultrasound examination and curettage if postpartum tissue has not shed on its own.