If your baby seems to fit that sweet little onesie one day and has it busting at the seams the next, it may not be your sleep-deprived eyes playing tricks on you. Baby growth spurts are aplenty in those first sweet 12 months.
Although growth spurts can happen at any time, it’s common for them to hit at about 10 days, between three and six weeks, and several times afterward. Three-month growth spurts, as well as six and nine-month growth spurts, are especially common. It's one of the reasons it's so important to have several sizes of baby clothes on your newborn checklist.
And when a baby growth spurt strikes, it can be fast and furious; babies can measurably gain weight and length in just 24 hours, says Michelle Lampl, a doctor and growth researcher at Emory University in Atlanta. Her studies show that tots can sprout as much as nine millimeters in length in just one day.
Wondering if your babe is in the midst of a spurt? Here’s what you might notice.
In the day or so before a big growth spurt, some babies sleep more than usual. “There are important physiological changes that happen during sleep that are essential for growth,” says Peter Nieman, a paediatrician and assistant clinical professor at the University of Calgary medical school.
Don’t wake her for feedings unless it’s within the first week and advised by your care provider. “She needs her rest, and she’ll make up for milk or formula she missed at her next feeding,” he says.Catherine Delahaye / Getty Images
Some babies prefer food to snoozing during a growth spurt. Even if she was starting to sleep longer stretches at night, your baby may suddenly want to eat around the clock again.
At about the three-month mark, Carrie Fisher, a Toronto mom of two, noticed a huge spike in her daughter Ramona’s appetite. “I knew she must be going through a growth spurt because she was inconsolable unless she was nursing,” Fisher says. “I thought there might be something wrong with my milk supply because she never seemed full.”StockPlanets/ Getty Images
If you’re breastfeeding, don’t worry, your body will keep pace with baby’s appetite. (Have real concerns that you’re not producing enough milk? Talk to your doctor.) Be sure to drink plenty of fluids and recruit your partner or a family member to help with everything that can’t be done with a babe in arms until the spurt passes.
If you’re using formula, increase the amount you’re giving very gradually—there is a danger of overfeeding. “If your baby starts spitting up more than usual she’s probably getting too much,” says Nieman.
Frequent fussing can be normal for a few days during baby growth spurts. “This can seem rather dramatic at the time, but it doesn’t last very long, and babies will calm down after their growth spurt,” says Lampl. Lots of cuddling and reassurance in the meantime will help to soothe her.Eva HM / Getty Images
You may feel like that growth spurt will never end, but it will. Most only last a couple of days. Not convinced that a growth spurt is to blame? Shifts in mood, feeding habits and sleep schedule can also mean that she’s getting sick, starting to teethe (if she’s older than three months) or just needing extra comfort due to a change in routine.
Talk to your doctor if you’re concerned that her symptoms might be something more, but don’t stress about exactly how much your baby is growing, or when, and don’t compare her size to that of other babies. At each wellness visit, your doctor will track her growth (measuring length, head circumference and weight).
As long as she’s gaining steadily and proportionally there’s no reason to sweat exact ounces or inches, says Neiman. “All babies grow at their own rate and speed—they know what they’re doing.”eggeeggjiew / Getty Images
Growth spurts usher in a wave of new physical skills and are typically the time when you will see changes in your child's physical abilities. Your baby may learn to roll over, crawl or even stand during this period. However, your baby will likely be extra tired or fussy during a growth spurt as well, which can lead to coordination difficulties.
It is important to be nearby as they practice their new physical skills during this time so that you can cushion the inevitable tumbles.Drazen Zigic / Getty Images
One of the most obvious changes during a growth spurt is an increase in height and weight. Infant growth spurts typically last only a few days, but you may notice a marked difference in your baby's size after this period. While your baby grows a little bit every day, at the end of a growth spurt, you may notice that her clothes are now too small or that you need to go up a size in diapers.
In general, your baby should double in weight by the time she's six months old and triple her weight by her first birthday.Ridofranz / Getty Images
In addition to buying larger jumpers and diapers, you might also find that your baby needs bigger sun hats and toques during her early growth spurts. In the first year, a baby's head grows 4 to 5 inches. During her first four months, specifically, your baby's skull will grow more quickly than at any other time in her life.
So, if you find a cap you really love, you might want to pick it up in a couple different sizes!urbazon / Getty Images
Much like a gangly pre-teen, your baby might display some previously unseen clumsiness as these physical skills begin to develop and this rapid growth takes place. Those limbs aren't where they were the day before, so it just makes sense that some flailing and new discovery of gravity might occur in this stage.SbytovaMN / Getty Images
Growth spurts also bring about changes in cognitive ability. You may notice your baby repetitively practicing a skill during this time, whether it's rolling over, laughing, hand-eye coordination or attempting to stand. During a spurt, your baby's brain is making loads of new neural connections that allow them to attempt things that were out of reach in the past—so enjoy those new smiles or extra laughs as she practices her newfound skills.Capuski / Getty Images
All the changes your baby is going through physically and mentally during these early growth spurts can, understandably, impact their energy levels when they're awake. Depending on where in a growth spurt they are, and other factors, you might find she's more engaged in her waking hours or less alert and playful than she used to be. The former makes sense with all these new connections her brain is making, while the latter can be due to being more tired or focused on other essentials, like feeding.d3sign / Getty Images
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