We're big fans of swaddling newborns to soothe them to sleep, and all that shushing and swaying, too. But another trick we've learned: Sometimes just breathing in a recognizable smell can calm a baby down.

Doctors have long known that a baby can distinguish the scent of his mom (and her milk) from that of other women. Research now shows that babies can recognize other smells they've been exposed to and that doing so can soothe them. A whiff of something familiar may enable your baby to think, "Oh, this is something I know," and that can be comforting, says Nathalie Goubet,Ph.D., a developmental psychologist at Gettysburg College in Pennsylvania.

In her study, Goubet exposed a group of babies to a vanilla scent 18 hours before their PKU screening (when blood is typically drawn through a heel stick) and had them smell the vanilla during as well as afterward. "They calmed down faster than babies who weren't exposed to the vanilla," says Goubet.

4 Easy Soothers:

• Don't sweat it if you didn't shower today. Your baby will love breathing in your natural aroma.
• Wear a tank so your baby gets skin-to-skin contact, then slip the top between his mattress and crib sheet.
• Massage your baby with the same lavender-scented cream before naptime.
• Try the "whole package." Have your baby smell something familiar, nurse him, swaddle him, and hold him close.