People with a Pear Body Shape have hips wider than their shoulders because their bodies store fat there and on the thighs. Pear shaped bodies carry their extra weight below the waistline, and do not seem to have as high a risk of developing health problems like diabetes, heart disease, stroke, high blood pressure, ... than people with an Apple Body Shape.
Pear shaped people usually lose fat in the upper body, so their overall shape doesn't change much when they lose weight.
With time, as insulin resistance worsens, people who store fat below the belt will start accumulating it above the belt too and they will start experiencing all of the more immediate health threatening problems their apple shaped friends likely experience right now.
The apple body shape (body fat is stored around the middle - i.e. abdomen, chest and surround internal organs, such as the heart) is linked with health problems such as coronary heart disease, diabetes, stroke, high blood pressure and gall bladder disease.
The shape is predominantly a male phenomenon; although women are more prone to develop an apple shape in mid-life, particularly after menopause.