Final answer:
After the expulsion of the fetus, the placenta and the remaining fetal membranes are known as the afterbirth. This constitutes the third stage of childbirth, and the afterbirth's complete delivery is vital for preventing complications such as postpartum hemorrhage. The postpartum period that follows includes further contractions that help the mother's body recover.
Step-by-step explanation:
Following the expulsion of the fetus, the placenta and remaining fetal membranes are collectively referred to as the afterbirth. The third stage of childbirth is characterized by the delivery of the afterbirth, which includes not only the placenta but also the associated membranes. The myometrium, which is the muscle layer of the uterus, continues to contract after the newborn is expelled, facilitating the separation and expulsion of the placenta from the uterine wall. It is crucial for the health of the mother that the entire afterbirth is delivered, as remnants can lead to complications such as postpartum hemorrhage. The obstetrician must ensure that the afterbirth is complete and intact to prevent such issues.
The expulsion of the afterbirth also marks the beginning of the postpartum period, a time of adjustment where the mother's body begins to return to a non-pregnant state. This period typically lasts around six weeks. During this time, continued uterine contractions help reduce blood loss from the placental site and assist in the process of involution, which allows the uterus and other abdominal organs to return to their pre-pregnancy locations.
If the placenta does not spontaneously expel within approximately 30 minutes, it is considered retained, and manual or surgical intervention may be required. Close monitoring during the postpartum period is essential to ensure the mother's health and well-being.