No, I will never tell you you're going to have the same hip size, bust, or even shoe size again. (columbusbirth.com)
Most backpacks can accommodate a wide range of hip sizes, but here's a tip: Adjust the belt size so that it straddles your hips about an inch above and below the line we just measured. (geekwrapped.com)
Fits waist / hip sizes from 68.5 cm (27 inches) to 140 cm (55 inches) so the same carrier can be used by more than one person. (babyslingsandcarriers.com)