Patient: How effective are birth control pills if they are not taken at the same time every day?
Doctor: Perfect use (taking it at same time everyday) results to ~99.5% effectivity of preventing pregnancy. Typical use (not ta king it at same time everyday) is only 90-95% effective. This may seem insignificant but a 5-10% chance of getting pregnant is NOT small. I hope I have answered your question and take care always.