It's the natural result of becoming a biped. I'm a healthy, fertile female, and the thought of having my baby grown inside a surrogate or outside of my body scares me. I don't have kids atm and may never do, but if I did I'd carry my children myself (assuming it's possible for my body to do so at the time).

I've heard all the horror stories, I've watched every video, and birth is completely terrifying-- but every mother describes it with an additional sense of gratitude. They're thankful their bodies can do it, that they have now a child they love, and also they feel so much stronger for it. There's a certain spiritual sense about going through so much pain and taking so much risk to give life to another human being. That feeling must be powerful.