LDs seem to some times start for me at periods when I'm half asleep or if I wake up for a moment then go back to sleep. Also LD can be trigered by external forces (like a beep on a wach that you use to remind you to do reality checks). I was thinking that maybe Sleep Apnea could triger a lucid dream. Sleep Apnea is when you stop breathing during sleep if it happens for long enough it can wake you up. I would think that if it wakes you up, while you were falling back asleep you would be more able to go into a lucid dream. Also if it didn't wake you up there might be some sort of happenings in your curent dream that you could use as a trigger to let you know you were dreaming. I don't have Sleep Apnea so I don't know what it feels like or if this would even be posible, I would like to here some opinons on this if anyone has Sleep Apnea or have any ideas.