Angelina Jolie adopting instead of having her own children

Interesting question. I guess it could be because she was was in a time in her career when she didn't want to gain weight or one of the other things pregnancies to do most women's bodies. But she'll probably never admit that. 

I think it has to do with her being a philanthropist. She obviously has no problem having children but adopted children from countries in need. She's Ambassador for the UN Refugee Agency and is a genuine humanitarian. She has adopted these children and it shows that there's no difference with the way she treats them with the way she treats her biological child.