I've been pregnant with twins, and personally I can't imagine going through that (including the C-section) for someone else. And you did it twice!!! Talk about a MAJOR sacrifice. I also can't imagine the feeling of letting go of the babies ... I imagine I would always wonder what their lives are like, etc. Do you ever have feelings like that plaguing you, as you wonder if they're healthy, safe, happy, etc.? Do you still feel a bond with them?
Also, did you end up with any health problems afterwards that you hadn't considered beforehand?