NuvaRing (etonogestrel/ethinyl estradiol vaginal ring) is a prescription medication used to prevent pregnancy. It is similar to oral contraceptives but comes in the form of a flexible ring that is inserted vaginally once a month. It works by stopping ovulation and altering the lining of the uterus and cervical mucus.
Benefits of NuvaRing include:
Very effective birth control method
Regular menstrual cycles
Lighter menstrual bleeding
Less menstrual pain
Decreased risk of ovarian or endometrial cancer (cancer of the lining of the uterus)

At this time, off-label NuvaRing uses include the treatment of the following conditions:
Heavy menstrual bleeding
Painful menstrual periods
Irregular menstrual periods

Prior to using NuvaRing, warnings and precautions concerning the safety of the contraceptive should be discussed with your healthcare provider. Tell your healthcare provider if you have high blood pressure, diabetes, or migraines before using NuvaRing. It is also important to know that NuvaRing may increase your risk of benign liver tumors, affect your cholesterol, cause high blood sugar, and change your menstrual bleeding patterns.

Warnings and precautions to be aware of prior to using NuvaRing include the following:

Smoking cigarettes greatly increases the risk of serious NuvaRing side effects (such as heart attacks, strokes, and blood clots). This risk is particularly high for smokers over the age of 35.

Combined oral contraceptives (which are very similar to NuvaRing) increase the risk of blood clots, strokes, and heart attacks. It is assumed that NuvaRing also has these risks. These risks are quite small for healthy, young nonsmokers. Make sure to tell your healthcare provider if you have ever had a blood clot, stroke, heart attack, or chest pain.

Combined oral contraceptives may also slightly increase the risk of breast cancer or cervical cancer. It is assumed that NuvaRing also has these risks.

Oral contraceptives increase the risk of benign (non-cancerous) liver tumors. Very rarely, these tumors can rupture and cause serious problems. It is assumed that NuvaRing also shares this risk. If you have liver disease, NuvaRing may not be the best choice for you.

Let your healthcare provider know if you have any sudden vision changes, as this may be a sign of a blood clot in the eyes (a possible side effect of NuvaRing and other hormonal contraceptives).

Hormonal contraceptives (such as NuvaRing) may make gallbladder disease worse. If you have had a problem with your gallbladder, NuvaRing may not be the best contraceptive method for you.

NuvaRing may increase blood sugar, particularly in women with diabetes. Your healthcare provider may need to monitor you more closely.

Hormonal contraceptives (including NuvaRing) can increase your blood pressure. This can be a problem if you already have high blood pressure.

NuvaRing can change your menstrual bleeding patterns. Some women have breakthrough bleeding (bleeding between periods), while others may not have a period at all. It is normal to have shorter and lighter periods while using NuvaRing. If you notice any unusual changes in your bleeding patterns, let your healthcare provider know. If you miss a period, you should make sure you are not pregnant.

NuvaRing can affect your cholesterol. Your healthcare provider may need to check your cholesterol levels after you start NuvaRing, especially if you already have high cholesterol.

There have been a few very rare cases of toxic shock syndrome in women who use NuvaRing. It is not clear whether these cases were due to NuvaRing, tampon usage, or other causes.

Sometimes, hormonal contraceptives may make depression worse. Let your healthcare provider know if you develop new or worsening depression symptoms.

Occasionally, NuvaRing (as well as any other hormonal contraceptive) can cause eye changes that make it more difficult to wear contact lenses.