A double-blind, randomized controlled trial on the use of a 50:50 mixture of nitrous oxide/oxygen in pain relief during suction evacuation for the first trimester pregnancy termination

Abstract

This prospective study assessed the role of a 50:50 mixture of nitrous oxide (N2O) and oxygen for pain relief during the termination of first trimester pregnancies by suction evacuation under conscious sedation. Ninety women undergoing suction evacuation up to 12 weeks of gestation were randomized by a computer-generated randomization list and allocated using sealed envelopes to receive the N2O/O2 mixture or air during the operation. Pain scores during and after suction evacuation, post-operative side effects and satisfaction level were compared. No statistically significant differences in pain scores, post-operative side effects and satisfaction levels were found between the two groups. N2O/O2 did not reduce the pain level during suction evacuation for the first trimester pregnancy termination under conscious sedation.