I didn't take any meds either and was ok during the pregnancy, but after the birth, I went into full blown post pard psychosis. If you know you are bi-polar, please let your docs know so they can monitor you and don't ignore any signs of strangeness. The hormones after giving birth does through you off kilter and the healing after giving birth is what you don't realize until after giving birth. A lot of stressors will trigger all at once. I don't want to scare you, but it is what I've experienced and I wouldn't want anyone to experience PPS.