sh77 - what an unsupportive and critical post. I'm sure it's done wonders to calm katy's nerves. 
Katy it sounds like you're very anxious - do you usually worry a lot, or is it pregnancy related? Were you like this in your previous pregnancies?
It sounds like you need lots of reassurance.
Still birth is really really rare, there's no reason to expect it. When you have your first baby, you're not really aware of the problems some women face, but by the time you get to your third, you've known three times as many women who know someone who knows someone x happened to, and then there's mn etc., and you just get to hear more tragic stories, and you become far more aware that these terrible things could happen to you.
Bear in mind bad news travels fast, and you never get to hear about the thousands of boring normal births, it's the sad ones that make an impact and, as jammie says, the worry is compounded by hormones and before you know it, you can't get the sad story out of your head!
And I know it's easy to say, but you can worry about anything you like till you're blue in the arse, sometimes you have to take a deep breath and say to yourself 'worrying doesn't change anything' and concentrate on what you can do - ie stay as healthy as possible and enjoy your pregnancy, and know that you are far more likely to have one of the boring normal births.