Jennifer Steinhauer New York Times News Service

In a world with few givens, there have always been a handful of life guidelines that American women could follow. Never date your best friend's ex. Always have at least one good pair of shoes. Get an annual mammogram starting at age 40.

In a world with few givens, there have always been a handful of life guidelines that American women could follow. Never date your best friend's ex. Always have at least one good pair of shoes. Get an annual mammogram starting at age 40.