True, but pregnancy and recovery is not a one size fits all kind of thing for any particular age group.
My friend R had a child very young and it nearly killed her. Many years later, she got pregnant and had her 2nd child at 41 and her 3rd child at 42, 11 months apart. She lost the baby weight quickly after the last one and was a much livelier, energetic mom that I was at 26. I really struggled later, when I had my 2nd at 35. I'm 41 and I may have not fully recovered yet!