(NEW YORK) -- Prince William and Kate Middleton may be royals, but as new parents, they're in for sleepless nights, messy diapers and the fear that they'll somehow break their baby. The first three months of life can be challenging, but new parents will surprise themselves at their ability to handle it, doctors said. "Babies don't come with an owner's manual," said Dr. Richard Besser, chief health medical correspondent for ABC News.
"A lot of it is just getting over the fact that, at some level, we are hard-wired to deal with newborns and able to meet their needs." Infants mostly spend their time doing three things: feeding, sleeping and pooping, Besser said. Although parents used to attempt to schedule these things, Besser said there's no need. The child will naturally let you know when and how often he or she wants to eat.
"When you're a new parent, you think everything your child does is because of what you do," he said. "When you have a second child, you get a better understanding of how much is out of your control."
For instance, Besser and his wife had difficulty getting their firstborn to feed, but his second child ate "like a champion." Later on, his older son turned out to be a picky eater. It's just the way he was.
For the first few months, babies will feed between eight and 12 times a day for 20 to 30 minutes at a time -- that winds up being up to six hours of breastfeeding per day, Besser said.
But thanks to breast pumps, dads should be helping out with that feeding, too, allowing moms to get much-needed rest, said Dr. Diego Chaves-Gnecco, a developmental-behavioral pediatrician at Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center.
Besser said new parents often underestimate how sleep-deprived they'll be and that it can take an emotional toll. That's why, even without postpartum depression, new moms can find a change in their mood. To cope, new parents will want to line up an "army of supporters" who can step in and give them a little break.
Babies start sleeping through the night at around 4 months old, but that doesn't mean parents can't take a night off and go to the movies when the baby has established good nursing habits. That usually starts between six weeks and two months.
"It's healthy," Besser said.
Some babies also cry more than others, said pediatrician Dr. Wendy Sue Swanson of Seattle Children's Hospital. What surprises many of her parents is that babies are often quiet the first few weeks, and then start to cry more and more until it "crescendos" at between 6 and 8 weeks old.
"One of the things that's hard for moms and dads at the beginning is being with friends whose babies are quiet," Swanson said. "It's really hard not to compare."
Since the No. 1 trigger for a parent to shake a baby is when it won't stop crying, Swanson said parents should recognize when they need a break.
"If a baby is really cranky and if you're getting really frustrated, the thing you can always do is you can always lay the baby down gently on its back in the crib and walk away for 10 minutes," Swanson said.
But if cries are associated with certain actions over and over again, like being put down or spitting up, it's a good idea to check with a doctor to make sure nothing else is wrong.
If parents notice their baby has a weak cry, a weak suck, yellow skin -- which can signal jaundice -- or a fever, it's time to call the pediatrician, Besser said.
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