Final answer:
The nurse should prioritize administering prescribed pain medication to a mother experiencing pain, alongside other secondary interventions such as relaxation techniques and frequent vital sign monitoring.
Step-by-step explanation:
The intervention that the nurse should prioritize when a mother is experiencing pain is administering prescribed pain medication. Before administering medication, it is essential to perform a thorough physical examination to determine the underlying cause of the pain and to assess the efficacy of prescribed pain relief. Encouraging relaxation techniques can also help manage pain, but typically, this would supplement medication, not replace it. Increasing the frequency of maternal vital sign monitoring is crucial for ensuring the mother's safety but is not directly related to addressing her immediate pain.
In the specific case of Janine, who is 41 weeks pregnant and admitted to the birthing unit with labor that is not progressing, an IV infusion of pitocin is started to stimulate uterine contractions and progress her labor. Pitocin is administered because it is similar to oxytocin, a hormone that induces labor.