I just logged on to ask the EXACT same question! I just had my second baby so I can answer you regarding my first.... Even with having FF from day one, I didn't get my period back until 4 months pp! I was very anxious and had PPD though, so maybe that had something to do with it. Every nurse and dr. I encountered said it would return around 4-6 weeks after birth so when it didn't I was pretty surprised. However, like most things in pregnancy/birth/postpartum recovery, "normal" varies widely. But I am very curious to know when other formula feeders had their cycles return... Oh, and as for this time, I'm 7.5 weeks pp and nothing yet. Lochia dried up around 5 weeks, returned very lightly for about 24 hours last week and nothing since. Not that I'm eagerly anticipating it...