Sleep experts say adults need between seven and nine hours of shut eye each night. But as many as one-third of people may not be getting enough, especially parents with newborns.

Dr. Harvey Karp, New York City pediatrician and author of “The Happiest Baby Guide to Great Sleep,”  told FoxNewsHealth.com that sleep deprivation can lead to unhealthy parents.

“It [lack of sleep] leads to post-partum depression, marital conflict, breastfeeding failure and unsafe sleep practices because you bring the baby into bed with you because you're so tired,” he said.

Harvey said some additional negative effects are obesity, poor productivity and absenteeism at work.

To ensure that new moms and dads get some sleep, Karp said parents can teach their baby to sleep better from the very first week of life with two important tips.

“Safe swaddling; arms down, not over-heating the baby and always sleeping on the back,” he said. “And the second part is white noise--all naps and all night. Those two things help to turn on the calming reflex, which gets the baby into a very profound sense of sleep.”

According to Karp, the goal is to get infants to have one four-hour-stretch of sleep a night, followed by a three-hour-stretch. He said after that, it shouldn’t be long before the baby can sleep five to seven hours at a time.

“Studies show that if you have a bedtime routine:  you do a bath, put on the pajamas, a little massage, and then read them a story or sing them a song, they go to bed,” he said. “That allows them to anticipate what's coming up next and eases them into sleep.”

Karp recommends starting the routine by turning the lights down before it's time for bed. He said even leaving on a television or computer can interfere with the brain’s natural sleep hormone, melatonin.

“So to be in bright lights and then sudden darkness is completely wrong and really interferes with sleep,” he said.

For more information on sleeping guidelines for infants, go to www.HappiestBaby.com.