My period usually arrives on Day 4 of the placebo pills, but arrived a day early, stopped, and then started a few hours later. It remained for the normal amount of time. I was on
medication, however, and I keep seeing differing statements about its effect on birth control. The Mayo Clinic says that medication doesn't effect it, but some other sites swear it does. Anyway, I did have my period and have not had sex since, informing my boyfriend that I didn't think I was ready for it.