 [ Symptoms ] could light colored or watery blood be a sign of anemia  my blood looks light red rather than bright red it seems thin it will not even completely stain a white t shirt my spouse has much thicker darker blood by comparison [ Disease ] i am assuming you are talking about a contraceptive pill since there are many different types of birth control the simple answer is that studies have proven that oral contraceptive use even for seven years does not adversely effect your ability to become pregnant when you choose