<iframe src="http://www.npr.org/player/embed/1146952/146952" width="100%" height="290" frameborder="0" scrolling="no">
NPR's Patricia Nieghmond reports on a new study showing that women who breast feed for longer periods are less likely to get breast cancer. That could help explain why breast cancer is more common in developed nations.
NPR thanks our sponsors
Become an NPR sponsor
Support The Programs You Love