A vaginal ring is a small, flexible plastic ring that you insert into your vagina to prevent pregnancy. It releases a steady, low dose of two hormones (an estrogen and a progestin) that stop ovulation and make it harder for sperm to reach an egg. With typical use, the ring is 91% effective at preventing pregnancy. With perfect use, that number climbs to over 99%.
How the Ring Prevents Pregnancy
The ring works through two hormonal mechanisms happening at the same time. The estrogen component prevents your ovaries from releasing an egg each month. Without an egg, fertilization simply can’t happen. Meanwhile, the progestin thickens the mucus around your cervix, creating a barrier that makes it much harder for sperm to enter the uterus. This two-layer approach is what gives the ring its high effectiveness when used correctly.
Because the hormones absorb directly through the vaginal lining, they enter your bloodstream without passing through your digestive system first. This means things like vomiting or diarrhea won’t interfere with how well it works, which is a practical advantage over the pill.
Types of Vaginal Rings
Three vaginal rings are approved for contraception in the United States, and they fall into two categories: monthly and yearly.
Monthly Rings (NuvaRing and EluRyng)
NuvaRing and its generic version EluRyng contain ethinyl estradiol and etonogestrel. You insert a new ring, leave it in for three weeks, then remove it for one week. During that ring-free week, you’ll typically get a withdrawal bleed similar to a period. At the end of the week, you insert a brand-new ring to start the next cycle, even if bleeding hasn’t fully stopped. Each ring is single-use and gets discarded after its three-week cycle.
Yearly Ring (Annovera)
Annovera contains segesterone acetate and ethinyl estradiol, and it’s designed to be reused for a full year. The schedule is the same: three weeks in, one week out. But instead of throwing it away, you wash it with mild soap and water, pat it dry, store it at room temperature, and reinsert the same ring for your next cycle. One Annovera ring covers 13 cycles, which makes it convenient if you don’t want to pick up a new prescription every month.
How to Use the Ring
Inserting the ring is similar to inserting a tampon. You squeeze it between your fingers to fold it, then slide it into your vagina. There’s no precise position it needs to sit in. The vaginal walls hold it in place, and most people can’t feel it once it’s in. If you can feel it and it’s uncomfortable, you can gently push it further in.
Timing matters. Insert and remove the ring on the same day of the week and ideally at the same time of day. For NuvaRing, that means inserting on a Monday and removing three weeks later on a Monday. One week later, on the following Monday, a new ring goes in. Annovera follows the same three-on, one-off rhythm but with the same physical ring each time.
The ring can stay in during sex, exercise, and bathing. Most partners don’t notice it. If you prefer, you can remove it during sex, but it should go back in as soon as possible afterward.
What to Do If the Ring Comes Out
Occasionally the ring can slip out during sex, tampon removal, or a bowel movement. If this happens, the clock starts ticking. If the ring has been out for less than 48 hours, rinse it in cool water and reinsert it. You’re still protected from pregnancy.
If it’s been out for more than 48 hours and you’re not in your scheduled ring-free week, wash it in cool water and put it back in right away. You’ll need to use condoms for the next seven days, because your protection may have dropped during that gap.
Common Side Effects
Most side effects are mild and tend to settle within the first two or three months of use as your body adjusts to the hormones. The most frequently reported include vaginal irritation or discharge, spotting between periods, headaches, nausea, breast tenderness, and a feeling of something being inside the vagina (which usually fades as you get used to it). Some people notice changes in weight or sex drive. Acne can improve for some users and worsen for others.
More serious side effects are uncommon but important to recognize. Pain or swelling in one lower leg, sudden crushing chest pain, severe headache with vomiting or vision changes, sudden difficulty speaking, or numbness in an arm or leg can signal a blood clot or stroke. These require immediate medical attention.
Who Should Avoid the Ring
The ring carries real risks for certain groups. Smoking while using the ring significantly increases the chance of heart attacks, blood clots, and strokes. This risk is especially high for people over 35 who smoke 15 or more cigarettes a day. If you smoke, the ring is generally not recommended.
People with a history of blood clots, certain heart conditions, or estrogen-sensitive cancers are also typically advised against using estrogen-containing contraceptives, including the ring. The estrogen component is the main concern, which is why your provider will ask about your medical history before prescribing one.
Does Body Weight Affect How Well It Works?
There’s some evidence that higher body weight may reduce the effectiveness of hormonal contraceptives, including the ring. One study found higher pregnancy rates among people weighing 70 kg (about 154 pounds) or more compared to those under that threshold. However, the overall evidence on this question is limited, and current guidelines don’t set a strict weight cutoff for using the ring. If this is a concern for you, it’s worth discussing with your provider to weigh the ring against other options like an IUD or implant, which aren’t affected by weight in the same way.
Ring vs. Other Hormonal Methods
The ring delivers the same types of hormones as combination birth control pills, but it requires far less daily effort. You deal with it twice a month (once to insert, once to remove) rather than remembering a pill every day. This is a big part of why perfect-use and typical-use effectiveness rates diverge less with the ring than with pills: there are fewer opportunities to make a mistake.
Compared to a hormonal IUD or implant, the ring is less effective in typical use and requires more active management. But it’s also fully reversible on your own terms. You can simply stop using it without a clinic visit, and fertility typically returns quickly. Annovera adds another layer of convenience since a single prescription covers an entire year without refills, though it does require the routine of washing and storing the ring between cycles.