I myself was a social smoker prior to taking Ortho-tryclen for about 2 years. Then, I was on the pill for about 2 years before I was hospitalized with a Deep Vein thrombosis(blood clot) in my pelvis/groin area. This does happen. I am presently on anticoagulants. I am a young healthy woman in early thirties until I was rush to the emergency room. Heed your doctor's warning.