Quartette (generic: levonorgestrel/ethinyl estradiol and ethinyl estradiol) is a prescription birth control medication used to prevent pregnancy.  

Quartette belongs to the next generation of extended regimen oral contraceptives and was designed to minimize breakthrough bleeding (BTB) between scheduled periods. Quartette contains two hormones, levonorgestrel and ethinyl estradiol, which belong to a group of drugs called hormonal contraceptives. These hormones prevent pregnancy by stopping ovulation and by altering cervical mucus and the lining of the uterus. Quartette is unique in that the dose of ethinyl estradiol increases at three distinct points over the first 84 days and the amount of levonorgestrel remains the same; this is followed by seven days of a lower dose of ethinyl estradiol.