No one of any age should have a C-section unless it is medically necessary, there is a lot more risk involved to both the baby and the mother, recovery time is much longer, risks of complications after are increased and it is harder to have a baby "naturally" afterward. I hope she isn't thinking this because she thinks she can avoid the pain of labor... she will still have to go through the pain of pre labor and she will have a LOT more pain afterward
She should try doing it the natural way first like if labor takes way to long a c-section would be best. (My aunt tried doing it natural but since her labor was taking to long her doctor did a c-section on her)
It all depends on her circumstances. She should talk to her doctor and ask all her questions. I realize she is scared and a bit embarrassed, but she doesn't need to be. Her doctor has seen and heard it all before and he/she would know her circumstances and can give her the best answers.