Final answer:
Labor is categorized into three stages: cervical dilation, the birth of the baby, and the delivery of the placenta. The first stage can vary greatly in duration and includes cervical effacement and dilatation up to about 10 cm. Subsequent stages involve delivering the baby with stronger and more frequent contractions and the delivery of the placenta.
Step-by-step explanation:
Stages of Labor
Labor is divided into three main stages. During stage one, the cervix thins and dilates to accommodate the passage of the baby. This stage is marked by cervical dilation from closed to about 10 cm and can take 6-12 hours but varies widely.
Stage two commences once the cervix is fully dilated. This stage involves the expulsion of the baby from the uterus. Contractions during this stage are more regular, frequent, and last longer—usually every 1.5-2 minutes, lasting for about a minute. The mother pushes by compressing her abdominal muscles to aid the delivery.
In the final stage, the placenta is delivered after the baby has been born. This occurs once the placenta has completely disengaged from the uterine wall. If labor stalls before stage two, synthetic oxytocin, known as Pitocin, may be administered to restart and maintain labor progress.