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 (first-ever users, switchers and restarters) 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.