Trial Information

Long-term Active Surveillance Study for Oral Contraceptives (LASS)

The LASS Study is a large, multinational, prospective, controlled, non-interventional,
long-term cohort study that follows a series of cohorts. The cohorts consist of new users
(starters and switchers) of three different groups of oral contraceptives (OCs): OCs
containing drospirenone (DRSP), OCs containing levonorgestrel (LNG) and OCs containing other
progestogens. A "non-interference" approach is used to provide standardized, comprehensive,
reliable information on these groups of OCs under routine medical conditions.

The main clinical outcomes of interest for the long-term follow-up are cardiovascular events
(e.g. myocardial infarction) and gynecological cancer. Regular, active contacts with the
cohort members (=active surveillance) provide all necessary information on health-related
events or changes in health status.

The study is based on the existing long-term EURAS cohorts who are still in follow-up. LASS
succeeds EURAS and prolongs the follow-up period for another five years. Total follow-up
time of members of the long-term cohorts will be between 6 and 10 years. By means of annual
contacts almost all relevant clinical outcomes will be captured. This will be accomplished
by contacting the relevant physicians and by reviewing relevant source documents in the case
of relevant clinical outcomes.