Levonorgestrel
"I had protected sex with my boyfriend on Sept. 16th at 1am but the condom broke. The following day, around 2pm I took Plan B One Step for the very first time. I read reviews before taking the pill so I would have an idea of what option to take. I didn't receive any symptoms at all, So I was convinced the pill didn't work so the panic began! This morning is when my period really kicked in. Very heavy bleeding and bad cramps. Overall, this pill really works and couldn't be happier to see my period."