Many women experience vaginal bleeding or spotting during pregnancy. This is a common symptom for many conditions and problems, some of which may be serious. There may be cause for concern depending on how much blood you’re passing, how far along you are in your pregnancy, and whether you have any other symptoms or pain. Keep reading to learn more about some of the most common conditions that cause bleeding during pregnancy. If you are concerned about any symptoms, call your health care provider. You may be asked to come in for blood tests or an ultrasound. Your doctor may or may not be able to diagnose a cause for the bleeding.