Effects of an extended flexible regimen of an oral contraceptive pill containing 20 μg ethinylestradiol and 3 mg drospirenone on menstrual-related symptoms: a randomised controlled trial

AbstractObjectives: The aim of the study was to assess the efficacy for menstrual-related symptoms of an extended flexible regimen of an oral contraceptive pill containing 20 μg ethinylestradiol and 3 mg drospirenone in comparison with a 24/4 d cyclical regimen of the same formulation.Methods: This randomised, non-inferiority, open-label, multicentre study was conducted in women aged 18–39 years. Their menstrual-related symptoms were assessed using the Penn Daily Symptom Rating (DSR17). Participants were randomised to use an extended flexible regimen of 20 μg ethinylestradiol and 3 mg drospirenone (EE/DRSPe.flex), comprising 168 consecutive days with a 4-d hormone-free interval (HFI, allowing for management of unexpected bleeding) or a conventional 24/4 cyclical regimen of the same pill (EE/DRSP24/4). The primary measure of efficacy was the percentage change in DSR17 total score from baseline to cycle 6. The secondary measures of efficacy were the percentage changes in DSR17 total score from baseline afte...