A Randomized Controlled Trial Comparing Use of Enthonox With Pethidine for Pain Relief in Primigravid Women During the Active Phase of Labor.

Background: The use of pain-relieving drugs during labor is now part of standard care in many countries throughout the world. Each method of pain relief has its own risks and benefits, variations in effectiveness, and availability and acceptability.

Objectives: This study aimed to assess the efficacy and safety of intramuscular pethidine as an analgesic during labor by comparing it to inhaled 50% nitrous oxide (Entonox).