A small, flexible ring that a woman puts in her vagina for three weeks, then takes it out for a week which is when she will have her period, then puts in a new one for three more weeks. It doesn’t need to sit in a particular position, it just needs to be as far back in the vagina as a woman can comfortably push it in. The Nuvaring contains estrogen and progestin. It works by preventing ovulation, by causing the cervical mucous to thicken to prevent sperm from entering, and it makes the endometrium thinner to help prevent implantation. The advantages can include more regular periods, decreased period flow, and less cramping. The disadvantages can include headaches, nausea, mood changes, weight gain, and vaginal discomfort. The failure rate is 3% to 6^%per year with typical use.