I might be pregnant and am on the pill. Is it dangerous to keep taking the pill until I take a pregnancy test? Can birth control pills cause a miscarriage?

Nobody has ever shown that the birth control pills will cause birth defects (or miscarriages).  That being said, it certainly is not a good idea to expose a developing fetus to the relatively high level of hormones that are in the birth control pill, and if we/you knew that you were pregnant we would certainly tell you to stop taking the pill.  My advice - do a home pregnancy test.  You will get the results in a matter of minutes and you won't need to stop taking the pill if it is negative.  In addition, you may wish to call the provider who prescribed the birth control pill for you, and tell them why you think you may be pregnant and ask them what you should do.