When it comes to gaining weight, it turns out that where you store your fat maybe more important than how much fat you have stored. There are two very different patterns of fat storage that have very different metabolic effects and excess body fat becomes an issue when it is stored in the wrong place.
The gynecoid pattern (typified as the pear shape figure) stores fat on the hips and thighs. This type of fat is stored below the skin in our subcutaneous tissue. It is found all over but in particular on the bottom, thighs and hips. This is typically a female pattern of fat storage as it is associated with oestrogen.