Why Baby is Very Fussy at 3 Months: 3 Reasons and 3 Tips

Very fussy 3 month old babyIf your baby is very fussy at 3 months old, you might dread the days. You are likely tired and frustrated trying to make your baby happy all day. If this describes you, this is common and there are three primary reasons this occurs. This post will share these 3 reasons and give you 3 tips to get through this frustrating stage based on 10+ years of experience as a sleep consultant.

Baby Very Fussy at 3 Months From a Growth Spurt

Growth spurts are common throughout the first year. They tend to occur around 7-10 days old, 2 weeks, 4 weeks, 8 weeks, 12 weeks (or 3 months), 4 months, 6 months, 8 1/2 months, 10 1/2 months, and 12 1/2 months old. Of course, every baby grows and develops on their unique timeline so you can’t expect them to start and end at the exact age but these are the average ages.

During a growth spurt, your baby is likely to be fussy for one major reason: hunger! Babies going through growth spurts typically get hungry very often to the point you feel like you are feeding them all day and night!

Babies going through a growth spurt also sleep a lot. They tend to get tired very quickly, take longer naps, and go to bed earlier.

Growth spurts last around 3-4 days to a week and once they are over, your baby’s fussiness should lessen.

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Sleep Regression and Developmental Leap

If your baby is very fussy at 3 months old and it comes on suddenly, they could also be going through a developmental leap. At 3 months old, many babies are becoming smoother with their physical movements and become more active. They might start rolling in one direction, from back to front, or from front to back. These developmental milestones can make your baby fussy.

In addition, this is a common age for babies to start breaking out of the swaddle. It’s a common time to stop swaddling.

During many developmental milestones, babies go through a sleep regression. During a sleep regression, your baby is likely waking frequently at night and taking short naps. The sleep regression around this time is the 4-month sleep regression. Some babies start this regression at 3 months old and the 4-month sleep regression lasts 3 to 4 weeks at its peak.

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Illness Leads to Very Fussy Babies at 3 Months

When you have a newborn, you typically keep visitors to a minimum to make sure no one unknowingly gives your baby a cold. However, eventually, you want more visitors and to get out of the house. So, a common reason for babies to be very fussy at 3 months is due to illness. It’s typically a cold though almost all children get RSV at least once in their first two years. My son got RSV within the first 3 months of his life, too.

In addition to viruses, if your baby is very fussy, you might consider if they have GERD or Infant Reflux. Taking a trip to the doctor might be in order as this is a very common condition diagnosed, now. And, if your baby is on medication, we have found that sometimes the dosage needs to be adjusted around this age. Babies grow very fast these first few months!

Also, if your baby has experienced colic, this is a common age for it to end. However, some babies don’t stop until closer to 4 months old.

What about teething?

Generally, teething doesn’t start until after 5 months old even if your baby is drooling. This is NOT as likely causing your baby’s fussiness.

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3 Tips to Get Through This Fussy Period

Assuming you’ve ruled out any health issues with your baby’s doctor, there are ways to get through this frustrating stage with your 3-month-old:

Feed Your Baby

This might seem like a no-brainer but we see some parents who are very rigid with their baby’s schedule. For example, those following 12 Hours by 12 Weeks will feed their baby only every 4 hours. During a growth spurt, though, that can lead to very long days of fussiness! In addition, in some cases, sometimes you will get short naps if your baby’s next meal is landing during the middle of a nap.

Consider increasing the size of your baby’s feedings in addition to feeding more often during a growth spurt. Or, it could be time to start solid foods with your doctor’s permission. Some doctors will add solid foods earlier if the baby has a big appetite. Generally, we try to wait until 6 months old so it depends on the baby.

Shorten Wake Windows

When your baby is growing and developing rapidly, they might get tired more quickly than they did a few weeks ago. Consider shortening the wake windows before naps and bedtime. The proper 3-month old schedule can do wonders for a fussy baby!

Wear Your Baby and Go for Walks

When babies are going through developmental leaps and/or illnesses, they often feel a bit more apprehensive about the world around them. They want to be close to you and sometimes distracted. Going for a walk with your baby in a carrier can be a great way to give them both!

Whether your baby is 3 months, 6 months, or 10 months old, they are going through a lot this first year. Hang in there and know that these stages pass quickly. As the saying goes, the days are long but the years are short.

The post Why Baby is Very Fussy at 3 Months: 3 Reasons and 3 Tips appeared first on The Baby Sleep Site – Baby / Toddler Sleep Consultants.


How Long Does the 4 Month Sleep Regression Last? And, How to Shorten It

How Long Does the 4-Month Sleep Regression Last?The 4-month sleep regression is an exhausting time in a family’s life. Your baby might be waking every 1-2 hours all night and taking short naps. And, if your baby is going through this, you’re probably asking yourself how long the 4-month sleep regression lasts. Based on my 10+ years as a sleep consultant, it doesn’t have to be as long as you think. In this blog post, I’ll share tips to get through the 4-month sleep regression.

What Is the 4-Month Sleep Regression?

The 4-month sleep regression marks the time when your baby stops sleeping like a newborn and starts sleeping more like an adult. Newborns spend a lot of time in deep sleep which is why they can sleep through so much in those early days. Once they go through this period of development, they change their sleep cycles which means they are sometimes only in light sleep and will wake more easily. So, the 4-month sleep regression is only the name we give this period of development. Do all babies go through the 4-month sleep regression? Yes, all babies go through this change and there isn’t a way to stop it. It’s actually a good sign your baby is developing appropriately!

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The most common signs of the 4-month sleep regression usually include one or more of the following:

  • Waking a lot at night (even when they used to sleep in long stretches) – waking every 1-2 hours at night is common.
  • Taking short naps of 20-30 minutes, sometimes 45 minutes.
  • Can’t be put down awake (or even asleep sometimes!) Baby wants to sleep only in your arms or a carrier/sling.
  • Irritability and Fussiness (though that can be simply due to sleep deprivation!)
  • Needing to be put back to sleep the same way each time (e.g. rocking or feeding back to sleep).

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How Long Does 4 Month Sleep Regression Last?

The 4-month sleep regression starts around 3 to 4 months old and lasts around 3-4 weeks at its peak. But since it’s a permanent change to how your baby sleeps, it doesn’t ever “end” in a traditional sense. Some babies will begin (or go back) sleeping fine again. But, others will continue to wake up frequently at night and take short naps. Over the past 10+ years, I’ve gotten phone calls or e-mails from parents of 4-month olds, 6-month olds, 10-month olds, 12-month olds, or 18-month olds with virtually the same exact sleep problems: frequent night-waking and/or short naps.

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How to Shorten This Regression

The only way to “end” the sleep problems this regression causes is to help your baby sleep better with their new sleep cycles. If you don’t want this regression to last months when it can last just a few weeks, you need to help your baby learn to put sleep cycles together.

Linking sleep cycles sounds simple enough when you’re an adult but for babies, it can be difficult. The most common reasons babies struggle moving into the next sleep cycle is due to hunger and sleep associations. A sleep association is a way in which your baby falls asleep. Because this is how they fall asleep, this is how they expect to fall BACK to sleep. Examples of sleep associations include rocking, feeding, bouncing, sucking on a pacifier, and driving in a car.

So, the key to shortening the 4-month sleep regression is simply to have your baby fall asleep the same way they will need to put themselves back to sleep. We typically do this by teaching babies to self-soothe with gentle sleep training. There are many methods to do sleep training or sleep coaching. The key is to find the one that works best for your baby’s temperament and personality. Please poke around and read through our many blog posts about this topic and more!

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