Should I wake up newborn to change diaper?

“There are very few circumstances where I'd recommend waking a sleeping baby to change their diaper.” Unless your baby has an open sore or serious diaper rash that requires monitoring, let them sleep. You really needn't worry about a bit of pee in the diaper.

While prolonged exposure to urine and feces can cause diaper rash in babies, it is not always necessary to wake your baby to change her diaper. Be sure to change wet diapers at least once every 2 to 3 hours and dirty diapers as soon as possible upon waking. If diaper rash occurs, change diapers more frequently and clean the diaper area more thoroughly with water, wipes, or bathing.