I could not recommend this book more highly.
Firstly, it's a quick and highly entertaining read - the author is witty, and the text is full of amusing anecdotes. I literally read the majority of the book in one sitting (admittedly I'm a fast reader, but I couldn't put it down).
Secondly, I love the central theme, which is that pregnant women tend to worry too much, when in fact "most pregnancies turn out fine; and when they don't, there was typically nothing anyone could have done to prevent it." This is the first book that had sufficient credibility to convince me not to worry about common pregnancy myths (like eating sushi). Basically, rather than stressing about what they should and shouldn't do, pregnant women should be relaxing and enjoying our pregnancies.
Finally, it's based on an extraordinary amount of research. To my knowledge, this is the very first time anyone has ever conducted a single, integrated analysis of the risks to pregnancy - not even any academic publication or government agency has ever taken on the monumental task of evaluating and quantifying every single potential risk to a fetus. The author has researched EVERY pesticide, EVERY pathogen, EVERY environmental contaminant that could possibly cause harm, and then taken only the few topics which are actually important to include in the main section of the book. As a result, this book bears almost no resemblance to typical pregnancy books, because it provides a top 5 list of behaviors that are the ones that are actually the most important.
I'll definitely be recommending it to all my expectant friends.