IRCT20200815048415N1 IRCT 2020-11-01 Ahvaz University of Medical Sciences The Effect of Inhaled Entonox on Pain in Pregnant Mothers The Effect of Inhaled Entonox on Pain in Pregnant Mothers 2020-10-06 anticipated 108 Complete https://irct.ir/trial/50568 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Used, Assignment: Parallel, Purpose: Supportive, Randomization description: Excel software rand function was used for randomization, Blinding description: After explaining the study to the participant and obtaining her informed consent, the participant is placed in one of the two intervention or control groups, but has no information about the type of drug received. 3 Normal delivery. Intervention 1: Intervention group: In the first group, women will be taught to inhale Entonox gas using a mask by placing their hands on their abdomen and touching or feeling uterine contractions, and in the interval between uterine contractions. Set aside.Entonox gas is a mixture of 50% oxygen + 50% N2O. Intervention 2: Control group: Oxygen use Patients were instructed to apply an oxygen-containing mask to the nose and breathe in it as soon as uterine contractions began, and to continue to do so until the uterine contractions were complete. This continues from 4-5 cm dilatation of the cervix to complete dilatation. Oxygen is 100% oxygen. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is There is no more information.