Combined hormonal contraceptive trials: variable data collection and bleeding assessment methodologies influence study outcomes and physician perception.

Initially approved for use in the United States nearly 50 years ago, oral hormonal contraceptives containing both estrogen and progestin have undergone steady improvements in safety and convenience. Concurrent with improvements in safety associated with decreasing doses of both steroids, there has been an increased incidence of unscheduled bleeding and spotting. There exist no standards regarding data collection techniques and methods, and reporting and analysis of bleeding and spotting events during combined hormonal contraceptive (CHC) trials. For the regulatory review of hormonal contraceptives, data regarding the incidence of bleeding and spotting events are not included in either of the traditional categories of efficacy and safety. Standardization of methods for collecting and analyzing data about cycle control in all clinical trials of CHCs is long overdue. Until such standards are developed and implemented, clinicians need to familiarize themselves with the techniques used in each study in order to provide correct information to their patients about the frequency of bleeding and spotting associated with different formulations and delivery systems.