| Methods |
Randomized controlled trial without blinding. The method of randomization and the use of allocation concealment are not described. |
| Participants |
458 women of childbearing age in Lima, Peru. Women were of low income and requesting the pill for socioeconomic reasons. More than 50% of the participants had been pregnant more than 4 times. |
| Interventions |
Biphasic levonorgestrel plus EE (LNG 50‐125 μg and EE 50 μg in a 10/11 day regimen) (preparation Alpha) versus
biphasic levonorgestrel plus EE (LNG 150‐200 μg and EE 30‐40 μg in a 7/14 day regimen) (preparation Beta) versus
triphasic levonorgestrel plus EE (LNG 50‐50‐125 μg and EE 20‐50‐30 μg in a 7/7/7 day regimen) (preparation Gamma). |
| Outcomes |
Primary outcome measures were pregnancy, cycle control, side effects, number and reasons for discontinuation. |
| Notes |
The report does not provide an a priori hypothesis or a sample size or power calculation. Large losses to follow up (40% to 54% in each treatment group). |
