I have a library of about 30 pregnancy/birth books that I occasionally reference. I read all of them when I was pregnant with DD. Last time I was pregnant, I read Birth Matters and that was all. This time Ive read a few twin books, and skimmed all my other books for their twin sections, but for the most part I dont feel too much like I need to read anymore books. I do plan to go through all of my books later in this pregnancy and read their c-section chapters just in case I wind up having to have one. I plan to make a pretty detailed section plan with my OB just in case, so I'd like to have as much information as possible.
One thing that I think I've learned the most from MDC is to question what I read. I remember that when I read all those books the first time I was pregnant, I soaked in all that information, and I knew it to be the truth. When I joined this website, and found that some of the authors that I had thought just knew everything there was to know about pregnancy and birth had quoted studies that we controversial or had been disproved before their book was published or that they had used statistics to prove a point, but not provided a fair and balanced argument for certain topics. A lot of the books I read would make you think that doctors are evil and the worst thing that can happen to you is for you to give birth in a hospital. I remember being terrified by all the information that I read about c-sections and awful OB's and hospitals. Things can be awful, but you can have a successful natural hospital birth too. Tons of people do it. It was really helpful for me to read about things online and find that just because someone wrote a book, doesnt mean it's 100% correct.
My favorite pregnancy book was From the Hips, mainly because it share the opinions of women from all different backgrounds, with all different parenting styles.
I liked Ina May's books for the birth stories, and I liked being able to reference What to Expect for what doctors and other professionals were probably going to tell me.