This is the third or fourth time this has happened in about a month (I guess that would average out to about once a week). My dd wakes up to nurse between midnight and maybe 2am (5.5 months old) and I don't have let down. She cries and I change her from one side to the other, back and forth, back and forth, and my body simply won't let down! There is no milk for her and she cries. Finally I put her paci back in her mouth and snuggle her and she falls asleep and is fine. Next time she wakes up to nurse, I have let down and all is well. It's SO strange and frustrating for me and her! Thankfully it's not a normal occurance, but what in the world could cause this? I do not take ANY medication, we co-sleep, I didn't eat anything unusual... I don't know??? I'm really curious as to why this happens. I don't know what I would do if she didn't go back to sleep and screamed to eat and I wouldn't have let down for her. Anyone else ever experience this or know what might cause it to happen??