Final answer:
The second stage of labor is when the baby is expelled, starting with full cervical dilation to delivery. It involves the baby's descent, birth, and delivery of the body. Duration varies, longer for first-time mothers and shorter for those with prior births.
Step-by-step explanation:
Second Stage of Labor and Its Phases
The second stage of labor is also known as the stage of expulsion. It begins with the full dilation of the cervix and ends when the baby is delivered. This stage is characterized by three phases: the descent of the baby into the birth canal, the birth of the baby, and finally, the delivery of the shoulders and body. The duration of the second stage can vary, but it may take minutes, hours, or even days. Factors such as whether the person has given birth before (nulliparous vs multiparous) can influence the duration. Typically, in each subsequent labor, this stage tends to be shorter for those with previous childbirth experiences. For nulliparous women (first-time mothers), the mean duration can be longer, often around two hours, while for multiparous women (those who have given birth before), it can last an average of about an hour.
During this stage, the uterus contracts and in most cases, the person giving birth will push while compressing the abdominal muscles to help expel the baby. If labor halts before stage two is reached, synthetic oxytocin, known as Pitocin, may be administered to restart and maintain labor.