"Quick-starting" of a Quadriphasic Contraceptive Pills, 1 - 3 mg Estradiol Valerate/ 2 - 3 mg Dienogest VS 20 mcg Ethinylestradiol/75 mcg Gestodene Focusing on Ovulation Inhibition: A Single-blind, Randomized Controlled, Non-inferiority Trial
"Quick-starting" of a Quadriphasic Contraceptive Pills, 1 - 3 mg Estradiol Valerate/ 2 - 3 mg Dienogest VS 20 mcg Ethinylestradiol/75 mcg Gestodene Focusing on Ovulation Inhibition: A Single-blind, Randomized Controlled, Non-inferiority Trial
The goal of this clinical trial is to learn if Estetrol/Drospirenone inhibit ovulation in quick-starting method. It will also learn about the safety of Estetrol/Drospirenone. The main questions it aims to answer are:
Does Estradiol valerate/Dienogest inhibit ovulation inferior to Ethinyl estradiol/Gestodene when starting on Day 7-9 of menstrual cycle? What are the impacts of Estradiol valerate/Dienogest on ovarian activities when starting on Day 7-9 of menstrual cycle? How does the cervical mucus change when starting Estradiol valerate/Dienogest on Day 7-9 of menstrual cycle? What are the adverse effects when starting Estradiol valerate/Dienogest on Day 7-9 of menstrual cycle? Researchers will compare Estradiol valerate/Dienogest to Ethinyl estradiol/Gestodene to see if Estradiol valerate/Dienogest inhibit ovulation in quick-starting method.
Take Estradiol valerate/Dienogest or Ethinyl estradiol/Gestodene starting on day 7-9 of menstrual cycle then every day for 1 pack of the pills.
Visit the clinic on day 1-2, day 7-9, and then every 2-7 days according to ultrasound finding (ovarian activities) until completing of pills to investigate
Inclusion Criteria:
Exclusion Criteria: