Most people think breast-feeding is instinctive, says Susan Will, lactation consultant at Sinai Hospital. "But I always tell a mother that parts of it are instinctual: The baby has an instinct to suck, and the mother's milk will come in. Putting the two together is a learned skill."
In the old days, it was a skill mothers passed on to daughters. But mothers in this generation were in large part raised on formula themselves -- even their own mothers can't show them how.
And it's harder than one might think. For example, new mothers might let the baby nurse at the nipple, which works fine when bottle feeding, but not when breast-feeding. "The baby's mouth should be open wide on the breast; you want the gums, the jaw, to be suckling. That tells the breast to make more milk," advises Ms. Vogelhut.