Caffeine and Effectiveness of Birth Control

I have read and heard that caffeine can affect the effectiveness of birth control. I drink soda and other caffeinated beverages regularly. I am worried that my birth control might fail and that I might become pregnant since I drink large amounts of caffeine regularly. Is this true?


I have also heard this about certain types of teas (i.e. hibiscus tea and green tea) not allowing your birth control to work effectively.