Prematurely born infants, living in a hospital’s Neonatal Intensive Care Unit (NICU), gained weight more rapidly when music was played. Music helped them learn how to suck at their mothers’ breasts more readily. It also reduced their overall stress levels, which may explain the other findings. One study found that female (though not male) infants’ stay in the unit would be decreased by 11 days if music were played, compared to no music. It is now standard for hospitals across the country to pipe calm, peaceful music into their NICUs.