Nitrous oxide for pain management of first trimester surgical abortion — a randomized controlled pilot study



      The objective was to determine feasibility of a study comparing mean pain scores between women randomized to nitrous oxide/oxygen (NO) versus oxygen+oral analgesics for trimester surgical abortion.

      Study design

      Pilot randomized controlled trial comparing NO (n=10) versus oxygen+oral analgesics (n=10). Feasibility of subject recruitment, and pain and satisfaction scores on a visual analog scale were evaluated.


      Fifty-seven percent of eligible women participated. Mean pain scores were similar between groups, and mean satisfaction scores were higher for the NO group (77.5 vs. 46.7, P=.048).


      The majority of eligible women agreed to participate in this study evaluating an uncommon pain control intervention.


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