I used Hypnobabies last time, and I just got the CDs out to listen to them again. It worked great for me, even though I didn't use them exactly as directed. I never was able to completely 'hypnotize' myself, but then again I always have trouble with totally letting myself go, trusting in the process, etc. However, I found that I was able to learn how to relax myself more. I found that the biggest help of the CDs was the confidence it gave me in my birth. I was already feeling really good and confident about it, but there were a lot of underlying doubts (I had had a hospital birth with pitocin and an epidural the previous time). So, I found that the CDs really worked on my confidence and trust in my body at a subconcsious level - which is what I really needed. By the birth and during labor, I was totally confident in my body and that I could do it at home.
I also listened to them going to sleep, and even when I listened to them when I wasn't planning on going to sleep - I usually fell alseep while listening. Which according to the book is totally fine, since it's working at a subconcsious level. It worked for me since there weren't that many times in the few months I did it that I was able to get through a whole CD without falling asleep, and it still gave me the confidence I needed. Maybe I did hypnotize myself, and I just fell asleep when I did :).
Anyway, I think you are supposed to listen to it when you aren't distracted, when you can get in the zone. Labor kind of provides its own "zone," so maybe it isn't as necessary to have total quiet then. But I would think it wise to not have any unnecessary things going on or unnecessary/unhelpful people there in later labor so you can get in "the zone" and not be stressed. I didn't actually have the tapes on during labor because everything went so quickly and we were not prepared - we didn't even have our camera or video camera at the birth because we couldn't find them. We were still preparing our birth kit during labor...etc. By the time I thought about using the CDs everything was still going really quickly, I didn't know where my CDs or the CD player was...so, but I really think having that confidence instilled in me helped more than anything. I had warned my husband not to listen to me if I said I wanted drugs or to go to the hospital and get an epidural, because I know that happens to a lot of people, especially during transition. However, I never once felt that way. I never once felt like I needed drugs or the hospital. I knew I could do it. I knew that everything was going normally. It never crossed my mind that I couldn't do it. So I really think that was totally the Hypnobabies, since the tapes repeatedly tell you that you can do it, it's a normal process, your body is made to give birth, etc.
One warning, though, you might want to tell your partner that everything they suggest on the tapes might not work for you. I didn't realize my husband had been listening to the tapes along with me - I thought he had been asleep. There is one part where in suggests your partner put his or her hand on your shoulder and say relax or something like that. I hadn't mentioned this to my husband or intentionally have him listen to it or practice it, because I didn't really think it would work for me, knowing me. Well, I was right. Even though I hadn't talked to him about it, he tried it during labor, and I kind of threw his hand off me and I might have snapped at him too. I didn't want him touching me during labor - at least at that moment, but he didn't try again...
I felt so bad right after I did it too, because I knew he was just trying to help, but that just didn't work for me. Anyway, because of that, he thought that Hypnobabies was crap and didn't work. I disagree, just that one exercise didn't work for me. He is supersensitive and touchy about that type of thing though.
Another thing about both hypnobabies and hypnobirthing is they talk to you about how it is not pain it is intensity. While you may think differently during labor (I've heard some women say - they lied, this is painful!), I think having that mindset really helped me during labor. I thought of it more like running a marathon or the intensity while lifting really heavy weights, or sprinting at the end of a race when you feel like you have no more energy left. It was about endurance, intensity, and working toward that goal. You know you are going to have a break, you know that at the end you will have a beautiful baby, and you know that this process of labor is making you stronger. I absolutely loved the experience of labor and birth, and I did feel that exhilaration like after I had put everything into a race or lifting weights. I really feel like Hypnobabies helped put me in that mindset, that this is not pain, this is intensity that comes with hard physical work.