I am nursing my third child (FF only the first two) I have actually started weaning though, (she is almost 4 mos old) I am only nursing at night now, when she wakes up.She gets formula the rest of the day including before bed and she sleeps very well. Goes down between 9-1030 and wakes to nurse only once usually between 330-5. But I can tell you that if you want to continue to nurse more, If you give formula before bed, it would probably be a good idea to pump as well just to keep your supply up. Once I hit about 3 formula feedings a day, my supply started to go down. by the time I got to just night feedings which only took about 2 weeks, I didn't even have to wear breast pads anymore and I don't really "feel" like I am making milk. Sometimes I have to check and make sure it didn't dry up without me realizing it. It's there, but I guess it's just enough for the one feeding at night. I was suprised at how quickly my body adjusted. Good luck, hope this helps