Final answer:
The second stage of labor, also known as the expulsion stage, is when the mother experiences the urge to push or bear down as the cervix is fully dilated and the baby moves through the birth canal.
Step-by-step explanation:
The urge to push or "bear down" occurs during the second stage of labor, which is known as the expulsion stage. This is the phase when the cervix is fully dilated, and the mother feels the need to push as the baby moves down into the birth canal and is eventually born. It is during this stage that the contractions are powerful and close together, which, along with the mother's efforts to push, help the baby to descend and be delivered. If the mother does not progress into this stage naturally, the administration of synthetic oxytocin, or Pitocin, may be recommended to facilitate the process.
Uterine contractions and the compression of abdominal muscles play a crucial role in aiding delivery during this stage. The process continues with the delivery of the baby, followed by the third and final stage, which is the expulsion of the placenta.