NuvaRing side effects including blood clots, stroke and heart attack have been reported by women using this relatively new form of birth control. Side effects of NuvaRing are associated with the hormone desogestrel which can cause changes in the blood clotting system allowing blood clots to form more easily. NuvaRing birth control was approved by the Federal Drug Administration (FDA) on October 3, 2001 and first marketed in the United States in July 2002. Nuva Ring is used by approximately 1.5 million women worldwide.