Two types of rings are available: A month-long ring that releases 15 mcg of ethinyl estradiol (estrogen) and 120 mcg of etonogestrel (progestin) a day and must be replaced each month A year-long ring that releases 13 mcg ethinyl estradiol (estrogen) and 150 mcg segesterone acetate (progestin) a day and must be replaced only once a year Both types of rings are typically left in place for 3 weeks, then removed for 1 week to allow for withdrawal bleeding.