Comparing Two Methods of Rectal Diclofenac Administration for Pain Management in Second Trimester Abortion: A Randomized Clinical Trial

Background & Objective: Pain is the most common side effect of induced medical abortion. However, the optimal analgesia method remains as a clinical challenge. This study aimed to compare the efficacy of two methods of administration of diclofenac as a prophylactic or a therapeutic in pain management in induced second-trimester medical abortion. Materials & Methods: This randomized clinical trial study was conducted upon pregnant women who were candidates for induced medical abortion and referred to a tertiary educational hospital between October 2019 and December 2020. Participants were divided into two groups based on the mode of diclofenac administration, which was either simultaneously with the first dose of misoprostol or after beginning of the pain. Pain severity, induction-to-abortion time interval, total misoprostol dosage, Hemoglobin concentration, length of hospitalization, and size of retained pregnancy products by ultrasound, and the cumulative dose of opioid usage were compared between the groups. Results: The severity of pain which was measured by a visual analog scale (VAS), residual of conceived products, hospitalization days, and the total misoprostol dosage were significantly lower (P<0.05) in the prophylaxis compared to the treatment group. Conclusion: Simultaneous administration of diclofenac with misoprostol as prophylactic method of pain management may be an optimal method in induced medical abortion in the second trimester.