This multicenter prospective cohort study evaluates the clinical efficacy and safety of dydrogesterone versus drospirenone and ethinylestradiol in adolescents aged 10-19 years with abnormal uterine bleeding-ovulatory dysfunction (AUB-O). Patients who meet the FIGO PALM-COEIN criteria for AUB-O, have complete baseline clinical data, and provide guardian consent with adolescent assent are enrolled. Participants are allocated to receive either dydrogesterone or drospirenone and ethinylestradiol according to routine clinical practice. The primary outcome is the 6-month menstrual normalization rate (cycle length 21-35 days). Secondary outcomes include breakthrough bleeding, recurrence, adverse events, and quality-of-life improvements. Follow-up is conducted during treatment and for 6 months after treatment cessation, during which menstrual normalization is evaluated based on changes in menstrual cycle patterns and examination findings. The findings may help clarify the comparative effectiveness and safety of these two hormonal regimens for long-term cycle management in adolescents with AUB-O.