This double-blind randomized control study was conducted to evaluate whether a nonsteroidal anti-inflammatory drug (NSAID) could act as an effective pain control method during first trimester suction abortion, and whether co-treatment of NSAID with misoprostol will decrease the efficacy of the cervical ripening effect of misoprostol. Subjects were randomized to receive misoprostol alone or misoprostol together with diclofenac sodium. Both groups of subjects suffered from similar incidence of preoperative side effects. Co-treatment of NSAID with misoprostol did not attenuate the cervical ripening efficacy of misoprostol. There was no significant pain reduction in the group treated with NSAID, except that a marginal benefit was found in the subgroup of multiparous women. About two thirds of the subjects in both treatment groups found that this was a satisfactory pain relief method during the procedure.