Heart rate variability, or HRV, is a metric often computed by a biofeedback machine to determine the regularity of a heartbeat. It compares the time between each beat, to determine how steady your heart performs.
1 When your baby is getting sleepy, put your baby in his or her crib in a quiet, darkened room. 2  This will help your baby learn to go to sleep in his or her crib. 3  Don't rock your baby to sleep after about age 4 to 6 months. 4  Rock your baby, but lay the baby down to sleep while he or she is drowsy but still awake. Give your baby a bath, sing lullabies, read a book, or tell a story. 2  These activities can help your baby relax. 3  They also signal that it is time to sleep. 4  Don't get your baby excited with active play right before sleep. 5  When your baby is getting sleepy, put your baby in his or her crib in a quiet, darkened room.
Newborn babies sleep a lot. Expect your baby to be asleep for up to 18 hours out of every 24 in his first few weeks (ISIS 2013). But he wonât sleep for more than one hour to three hours at a time, day or night, as he will need frequent feeds (ISIS 2013, NSF nd). This means that you can expect some sleepless nights, especially at first.