Riding Horse When Pregnant

Do you ride horses when you are pregnant? 

I've not done it before but I have known people who do.  Personally, I wouldn't risk a fall so I could never do it. 

If I were to get pregnant again (and it may not even be possible if we did want another child...which we aren't trying for), I think I'd just be content with spending time with my horse, taking my prenatal vitamins, and waiting until after giving birth to get up on a horse again.  It'd be awful to fall or be thrown from a horse and lose a baby.  I don't think I'd be able to forgive myself.