Backaches

Most women, when they first use the system, experience backache during sleep. This may be because we aren't accustomed to sleeping on our backs in such a rigid position all night.

Rin's advice:

First, the backache won't last forever, so don't despair. To manage the pain while you do have the backache, you can try the following:

Put a pillow under your knees, and don't use one under your head. This presses the lower back into the bed.
Put a cold-pack (I use the kind that comes with padded lunch boxes) under your back. I found this made the pain bearable enough for me to sometimes fall back to sleep.
Vary your sleeping location. I slept half the night in bed, and then when I woke up with a backache, I'd move to the couch. On the couch, I could wedge myself into the corner with pillows (it's an L-shaped set of couches, actually). In fact, at week 17, I still find it easier to sleep on the couch some nights.

PMB10's advice:

I rarely slept in my Brava, but when I did I would not only put a pillow under my knees, but found that a pillow under each arm also helped tremendously. It helps hold your arms up more even with those big domes. I found when I allowed my arms to rest back on the mattress (I was in L's and XL's) it pulled the domes and was painful.