http://www.askdrsears.com/topics/pregnancy-childbirth/tenth-month-post-partum/bonding-your-newborn/rooming-vs-nursery-care
Rooming-in. This is the option we encourage most mothers and babies to enjoy. Full rooming-in allows you to exercise your mothering instincts when the hormones in your body are programmed for it. In our experience, and that of others who study newborns, mothers and babies who fully room-in enjoy the following benefits:
Rooming-in babies seem more content because they interact with only one caregiver—mother.
Full rooming-in changes the caregiving mindset of the attending personnel. They focus their attention and care on the mother, who is then more comfortable and able to focus on her baby.
Rooming-in newborns cry less and more readily organize their sleep-wake cycles. Babies in a large nursery are sometimes soothed by tape recordings of a human heartbeat or music. Rather than being soothed electronically, the baby who is rooming-in with mother is soothed by real and familiar sounds.
Mother has fewer breastfeeding problems. Her milk appears sooner, and baby seems more satisfied.
Rooming-in babies get less jaundiced, probably because they get more milk.
A rooming-in mother usually gets more rest. She experiences less separation anxiety, not wasting energy worrying about her newborn in the nursery, and in the first few days newborns sleep most of the time anyway. It's a myth that mothers of nursery-reared babies get more rest.
Rooming-in mothers, in our experience, have a lower incidence of postpartum depression.
Rooming-in is especially helpful for women who have difficulty jumping right into mothering. One day while making rounds I visited Jan, a new mother, only to find her sad. "What's wrong?" I inquired. She confided, "All those gushy feelings I'm supposed to have about my baby—well, I don't? I'm nervous, tense, and don't know what to do." I encouraged Jan, "Love at first sight doesn't happen to every couple, in courting or in parenting. For some mother-infant pairs it is a slow and gradual process. Don't worry your baby will help you, but you have to set the conditions that allow the mother-infant care system to click in." I went on to explain what these conditions were.
All babies are born with a group of special qualities called attachment- promoting behaviors—features and behaviors designed to alert the caregiver to the baby's presence and draw the caregiver, magnet like, toward the baby. These features are the roundness of baby's eyes, cheeks, and body; the softness of the skin; the relative bigness of baby's eyes; the penetrating gaze; the incredible newborn scent; and, perhaps, most important of all, baby's early language—the cries and precrying noises.
Here's how the early mother-infant communication system works. The opening sounds of the baby's cry {C} activate a mother's emotions. This is physical as well as psychological. Upon hearing her baby cry, a mother experiences an increased blood flow to her breasts, accompanied by the biological urge to pick up and nurse her baby. This is one of the strongest examples of how the biological signals of the baby trigger a biological response in the mother. There is no other signal in the world that sets off such intense responses in a mother as her baby's cry. At no other time in the child's life will language so forcefully stimulate the mother to act.