While it is not supposed to happen and isn't common, some women do end up conceiving after tubal ligation. Depending on how you have it, if you had clamps, they could have come undone. Or if they severed your tubes, they could have formed scar tissue that made a tube of sorts that sperm can get through. The unfortunate thing is that pregnancy after tubal ligation has a really high rate of being ectopic of a tubal pregnancy. Which is not viable and can be life threatening to the mother. So, if you suspect pregnancy, you should definitely take a test and/ or be seen. They can also help you if you are having irregular bleeding/menstruation so it is probably time to see a doctor to discuss this. Let me know what happens, okay?