Final answer:
The delivery of the placenta, or afterbirth, is the last stage of childbirth, where it is expelled through the vagina. If it does not come out spontaneously, manual removal may be attempted.
Step-by-step explanation:
The last stage of childbirth is the delivery of the placenta, also known as the afterbirth. After the baby is born and the placenta is completely disengaged from the uterine wall, it is expelled through the vagina. If the placenta does not come out spontaneously within about 30 minutes, it is considered retained and the obstetrician may attempt manual removal.