One of the things that I really loved about our childbirth prep classes was the scientific aspect - what the uterus and cervix are actually up to during contractions/surges/waves, how the baby's position impacts delivery and the type of labor you have (back, etc).
Anyway, I keep a blog for my family to read. In it, I write about a lot of these things, like how happy I am that Baby seems to really like being in the left anterior position, etc.
My mom called me last weekend and said, "I thought that all babies were born facing upwards (i.e. 'sunny-side up') until I read your blog!" She had all four of us naturally, in a hospital, and we were all posterior! She said that she had really bad back labor, but that's how she thought it was for everyone! Every time she would deliver one of us, the doctor would have her stop through a pushing contraction so that he could "turn the baby."
I just can't believe that her doctor (the same one delivered all of us) never told her to work on positioning before labor! She went 30 years thinking that all babies were born this way!
At the same time, it's very inspirational to me that my mom could get through back labor, having to be in the lithotomy position the whole time, and delivering all of us posterior!