Does size matter? Yes, according to researchers at University College London, who found that changes in a woman’s skirt size correlate to her breast cancer risk after menopause. Obesity, particularly in the form of belly fat, is a known risk factor. And while women don’t normally recall their twenty-something body mass index, they often remember their skirt size. The study determined that going up a full size each decade resulted in a 33 percent increase in cancer risk.