I know birth control is supposed to stop ovulation. but how often does bc actually prevent ovulation? are there any signs to tell you are ovulating ?

Birth Control: Not all birth control stops ovulation. Some pills just prevent implantation. Iuds prevent implantation after conception, etc. There are lots of choices out there. But, in general if taken correctly birth control works very well at preventing pregnancy.

Birth control pills,: Novaring and depoprovera shots prevent ovulation, whereas an iud prevents implantation. Most women do not notice when they ovulate and others get pain and notice a change in vaginal secretions.