The number of women buying, selling and sharing breast milk is growing rapidly. But it can be a risky purchase, scientists say, because a mom can't tell by looking at the milk whether it's safe and nutritious for her baby.
A lab technician at the Mothers' Milk Bank Northeast in Newton Upper Falls, Mass., prepares donated breast milk for pasteurization in August 2012. The process kills harmful bacteria.
Elise Amendola/Associated Press