What are the side effects of starting a new bc or is it early signs of pregnancy?

Most have none: Most women have no side effects, with the benefit of no pregnancy; risks of side effects are less than in pregnancy. In the 1st few mos irregular bleeding can occur that gets better over time. Others include breast tenderness, nausea, mood changes, headaches. 1 serious potential risk, altho rare, is a blood clot in your leg or traveling to your lungs, again, less likely than in pregnancy.