When I was pregnant with Rio, my favorite books were The Thinking Woman's Guide to a Better Birth and Journey Into Motherhood. The Thinking Woman's guide was super informative and I would recommend to any mom, whether it's your first baby or you're a veteran mama.
Journey Into Motherhood is a collection of inspirational natural birth stories as well as affirmations, secrets and techniques for easing birth. I loved the format of this book because I could read one short story a night before bed and I always went to be with positive thoughts!
Another motivational read is The Daily Soul Sessions for the Pregnant Mama. This book is just a page a day throughout your pregnancy, so anyone has time for it. A fun and inspiring read that helps you through your pregnancy.
Hypnobirthing is an amazing book for anyone who is striving for a natural birth. I didn't take a hypnobirthing class, but reading the book and listening to the affirmations helped me
Right now I'm reading Ina May's Guide To Childbirth. Very interesting and a great resource.
Lastly, my husband read this during my first pregnancy and he recommends it to all first time dads.
Hope this list helps! You got this mamas!!