Do all cats quit eating before giving birth?

I'm expecting a litter any day now. I've never had a cat whose had kittens before, so I'm on pins and needles waiting. I've read cats will quit eating prior to giving birth, do all cats do this? I swear my cat will have her kittens any minute (I've been thinking this for the past 2 weeks), but she eats like a pig still.

Her stomach is so swollen that I swear she can't get any bigger. I can feel the babies move in her so well that I swear I can make out heads and feet and bodies.

What is the surest sign she's in labor?

Any advise is appreciated.

Nope, not all. Butterball ate normally the whole day before giving birth right before midnight. The kittens were extra active in her belly just hours before she gave birth too. I've heard they don't move around as much right before birth, but this isn't so for all cats.

My girl actually snacked between delivering babies. *grin*