Conditions: Contraception
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 742
Healthy volunteers: no

Brief summary:
The purpose of this study is to investigate if drug doses lower than the one released from Mirena® would be as effective for contraception as Mirena®. Subjects participating in the study will be randomly assigned to be inserted with any of the three different intrauterine systems (IUSs). The IUSs are nearly alike except that the amount of hormone released from them is different.

Detailed description:
The study has previously been posted by Schering AG, Germany. Schering AG, Germany has been renamed to Bayer Schering Pharma AG, Germany.

Bayer Schering Pharma AG, Germany is the sponsor of the trial.

Although the title of the study describes "open", it was in fact single-blinded.

Issues on side effects are addressed in the Adverse Event section.

Arms:
arm 1: Levonorgestrel intrauterine contraceptive system (LCS) releasing 12 microg/24h in vitro arm 2: Levonorgestrel intrauterine contraceptive system (LCS) releasing 16 microg/24h in vitro arm 3: Levonorgestrel intrauterine system (IUS) releasing 20 microg/24h in vitro

Interventions: intervention 1: Levonorgestrel IUS (BAY86-5028, G04209B) intervention 2: Levonorgestrel IUS (BAY86-5028, G04209C) intervention 3: Levonorgestrel IUS (Mirena, BAY86-5028)
Intervention descriptions: intervention 1: Levonorgestrel intrauterine contraception system (IUS) releasing 12 microg/24 h in vitro, to be used for three years intervention 2: Levonorgestrel intrauterine contraception system (IUS) releasing 16 microg/24 h in vitro, to be used for three years intervention 3: Levonorgestrel Intrauterine contraception system (IUS) releasing 20 microg/24 h to be used for three years

Protocol document: