I 5th Up the Duff by Kaz Cooke easy to read and funny in parts, I didnt like what to expect when you are expecting at all.

another recommendation is Miriam Stoppard - easy to read and pics (not graphic ones just informative for each stage of pregnancy and then taking care of baby. Her new book Bonding with your Bump I am going to buy and her older other books - I have Conception Pregnancy and Birth.

for reference books I use Baby love by Robyn Barker which is awesome too.