• Shnaw Abdulwahab Karim Sulaimani Maternity Teaching Hospital, Sulaimani, Kurdistan Region, Iraq.
  • Rozhan Yassin Khalil Sulaimani Maternity Teaching Hospital, College of Medicine,University of Sulaimani, Kurdistan Region, Iraq.




Entonox, Labor Pain, Pain Relief, Pethidine, Sulaimani



Labour pain is one of the acute severe pains women suffer during their lives. Various methods have been tried to manage it.


The aim was to compare analgesic effects and outcomes of Entonox versus Pethidine for labour pain.

Patients and Methods

The non-blinded Randomised clinical trial was performed on 221 pregnant women admitted to the Labor Ward of Sulaimani Maternity Teaching Hospital from January 2020 to January 2021. Women were randomly allocated the group I of 111 pregnant women who received Entonox and group II of 110 pregnant women who received 1 mg/kg of Pethidine. A visual analogue scale (VAS) pain score was used before 30 and 60 minutes after drug administration. In addition, a Neonatal Apgar score of one and five minutes was recorded.


There were no significant demographic feature differences between both groups. Mean pain scores before drugs were 7.8±1.6 and 7.8±1.3 after 30 minutes were 4.6±1.6 and 5.7±1.6, and after 60 minutes were 3.8±1.5 and 3.9±1.6 for Entonox and pethidine groups, respectively. Entonox decreased pain score better than Pethidine after 30 minutes (p-value of <0.001); however, Pethidine decreased pain score better than Entonox after 60 minutes (p-value of <0.001). Mean Apgar scores in 1st minute were 8.6±.87 and 8.41±1.28, and in 5th minute was 9.84±.37 and 9.62±.82 for Entonox and pethidine groups, respectively. Significant association of drugs with Apgar score at 5th minute was found. 


Entonox was better for acute pain management within 30 minutes; Pethidine was better for longer than 60 minutes.


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How to Cite

Karim S, Khalil R. ENTONOX VERSUS PETHIDINE FOR PAIN RELIEF DURING THE ACTIVE PHASE OF LABOR. JSMC [Internet]. 2022 Jun. 21 [cited 2024 Jul. 21];12(2):125-33. Available from: https://jsmc.univsul.edu.iq/index.php/jsmc/article/view/jsmc-10352

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