| Methods |
One site in Thailand.
Three‐month wash‐out period for OC users. 12 treatment cycles.
Unblinded. |
| Participants |
Women aged 18 to 35 years, willing to use contraception for over 12 complete cycles with at least a three‐month washout period.
Excluded contraindications to OC use; liver, vascular or metabolic diseases; tumor; pregnancy; unclassified and genital bleeding. |
| Interventions |
EE 20 µg and gestodene 75 µg (N=76) versus EE 30 µg and gestodene 75 µg (N=74). |
| Outcomes |
Contraceptive efficacy, cycle control, and side effects.
'Regular' cycle was defined as periodic withdrawal bleeding every 28±7days.
'Breakthrough bleeding' was defined as intermenstrual bleeding that did not require sanitary protection. |
| Notes |
Randomization method not reported.
76% (114/150) completed study. |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Allocation concealment (selection bias) |
Unclear risk |
Not reported |
