###Human: Is it normal to have bleeding in between periods? ###Assistant: Hello. Any type of hormonal contraception may cause irregular bleeding that can be unpredictable in nature. If a birth control method is changed or if pills are missed, unscheduled bleeding can also occur. All birth control methods can fail, even with perfect use and unusual bleeding can also be a sign of pregnancy. A home pregnancy test is a good idea to make sure this is not the case. Upper back pain an unusual side effect of birth control, but cramping may be normal if it is during a period. Cramping or pelvic pain in the setting of abnormal or irregular bleeding could be caused by many things including ovarian cysts, early or abnormal pregnancy, urinary tract infections, sexually transmitted infections or PID (pelvic inflammatory disease). She would need an exam and further testing in order to confirm the exact cause of her symptoms.