Analysis of failure in medical abortion.

Medical abortion opens a new choice to women wishing to terminate a pregnancy. Increasingly, providers in the developing and developed world will begin to offer this option. Yet, the nomenclature and concepts used for measuring failure of surgical abortion are not directly adaptable because of important differences inherent in the method and in the way it is offered in a given setting. We propose that failures in medical abortion should be defined as a surgical intervention (whether vacuum aspiration or dilatation and curettage) performed for any reason. Such instances may be further classified into three types: user choice interventions, provider choice or error interventions, and true drug failures requiring intervention. Further description and examples of each type are given.