Like nearly all forms of birth control, Lillow does cause some side effects. However, for most women, these are mild and don't cause any problems. Some of the most common symptoms include vomiting, nausea, breast tenderness, and trouble wearing contact lenses. Most of these symptoms subside after about three months when your body gets used to the hormonal changes from Lillow.
You may also experience changes to your menstrual cycle. Your periods may become irregular, or you could skip them altogether. Always let your doctor know if you skip more than two periods in a row, as this could be a sign of a more serious problem.