I have been taking birth control pills for about 15 yr's (mostly on, though off for short periods of time) It's said that they can make your periods regular, which I find that they do. But as someone who is now 32 and has SVT (supraventricular tachycardia) and has "done everything right", eaten well, didn't use drugs, etc. I feel young to have this (I had my first noticeable episode at 28). I don't know what caused it and never will, was it over the counter cold medicines (which I didn't use often), was it the pill? Chocolate? Bad luck? Who knows, but if you are already having heart issues (and I can tell you from experience almost no one will take you seriously with heart problems when you are young) be careful about the pill. If I had definitively known it could cause my heart to act this way I never would have taken them, unfortunately we probably can't definitively know.