Enh, the media and medical industry in the U.S. (specifically) seem bent on making pregnancy sound dangerous and fragile and impossible to accomplish successfully without the advice of eleventeen different books and doctors and special precautions.
In fact, while not all pregnancies work out (believe me, I have been there more than once) there is no evidence-based reason to believe that "doing something wrong" is a common cause of miscarriage (except for just a few things, like eating extremely poorly, exercising beyond exhaustion, etc).
Many things that American pregnancy books conventionally warn you against are actually VANISHINGLY RARE - listeriosis from unpasteurized cheese, toxoplasmosis from cat poo, things like that - or it's something that you already knew you shouldn't be doing, like using street drugs.
Worrying yourself into a lather is probably as big a threat to a pregnancy
Be sensible (basically: hand washing); stay active and fit; eat in a reasonably healthy fashion; and let your body do what bodies do when they're pregnant. You can't control everything (especially not gestation!) and it generally turns out okay in the end. And when it doesnt it is almost never something you could have prevented anyhow.
Oh, and if you are a worrywart, stay away from the shelf of pregnancy books in the library, or take them all with a BIG grain of salt. Or better yet, read European pregnancy books, they are on the whole less hysterical and better grounded in reality
Good luck to you,
Pat
