The two study cohorts will consist of new users of Intrinsa® in combination with estrogen therapy and estrogen therapy without simultaneous use of Intrinsa®, respectively. After study entry cohort members will be followed for a period of five to eight years for rare serious safety outcomes. Regular, active contacts with the cohort members by the ZEG study team (=active surveillance) will provide the necessary information on health-related events or changes in health status. All cohort members will be contacted at 6 and 12 months after study entry, and then every 12 months.