3-month-old baby: Development, milestones and growth

Nikki Stevenson
Nikki Stevenson
Nikki is a parenting writer and a mom to three wild boys who keep her on her toes (and occasionally make her question her sanity). With over 15 years of experience in the parenting industry, she has more tips and tricks than Mary Poppins on speed dial. When she's not typing away at her keyboard, you can find her sipping on coffee, hiding in the bathroom for five minutes of...
img Medically reviewed by Faith Hobson
Created on Jun 06, 2024 · 11 mins read

You've made it through the first three months – congrats! By now, you're probably getting the hang of this whole parenting thing (or at least pretending really well).

Now that your little one is a 3-month-old, things are getting interesting. From adorable gummy smiles to those not-so-fun nappy blowouts, every day is an adventure. In this guide, we’ll take a closer look at what’s in store for you and your baby at this stage. So, if you have a moment to yourself (which is scarce these days), let’s dive in.

Your 3-month-old baby's development

As your baby reaches the three-month milestone, you’re likely noticing significant changes in their development. Physically, they’re becoming more robust, with muscles gaining strength and coordination improving by the day. Their cognitive and social skills are also blossoming, as they begin to interact more with their surroundings and respond to familiar faces and voices. Let’s delve deeper into what you can expect at the 3-month-old stage of your baby’s journey.

3-month-old physical milestones

At 3 months old, your baby is making remarkable progress in their physical development and might reach key gross motor milestones.

Improved head control
Your baby can now hold their head steady when supported in a sitting position, demonstrating your baby’s neck strength and control have increased.

Increased muscle tone
Muscles throughout their body are strengthening, allowing them to make more purposeful movements and engage in activities like reaching and grasping.

Enhanced eye-hand coordination
Your 3-month-old baby’s ability to coordinate their eye movements with their hand movements is improving, enabling them to reach for and grasp objects more accurately which is one of the important baby milestones.

Beginning of rolling over
While not all 3-month-old babies roll over at that exact age, some may start to roll from their back to their side or even onto their stomach as they gain strength and confidence in their movements.

Improved visual tracking
Their ability to visually track moving objects continues to develop, enhancing their depth perception and hand-eye coordination.

These physical milestones are signs of your baby’s growing strength and coordination, laying the foundation for further motor skills development in the months to come.

3-month-old baby weight and length

As your baby reaches the 3-month mark, you may be curious about their growth in terms of weight and length. Here’s what you can expect from the baby milestones.

Weight gain: On average, babies continue to gain weight at a steady rate of around 150 to 200 grams per week during the first few months of life. As a 3-month-old, your baby’s weight may have increased by approximately 1.8 to 2.4 kilograms since birth.

Length: Similarly, your baby’s length or height will continue to increase gradually. By three months, your baby may have grown by around 9 to 10 centimetres since birth. These measurements provide insights into your baby’s overall growth and development.

Doctor visits: Regular check-ups with your paediatrician or your child’s healthcare provider are essential for monitoring your child’s development and growth. During these visits, your doctor will measure your baby’s weight, length, and head circumference, comparing them to standard growth charts to ensure they are progressing as expected. If you have any concerns about your baby’s growth or feeding habits, don’t hesitate to reach out to your paediatrician.

Feeding habits: Your 3-month-old baby’s weight gain is closely linked to their feeding habits, whether they are breastfed, formula-fed, or a combination of both. Breastfed babies may have a more gradual weight gain pattern compared to formula-fed babies, but both are considered healthy as long as they are gaining weight steadily and meeting developmental milestones.

3-month-old feeding milestones

At 3 months old, your baby’s feeding habits may continue to evolve as they grow and develop. You might experience changes like:

Increased feeding frequency: As your baby grows, they may show signs of increased hunger and a greater interest in feeding. They might want to nurse or take a bottle more frequently throughout the day.

Longer nursing or bottle-feeding sessions: With improved coordination and sucking ability, your baby may be able to nurse or bottle-feed more efficiently, leading to longer feeding sessions. This allows them to consume larger quantities of milk or formula in a single feeding.

Established feeding routines: By 3 months, many babies have established a more predictable feeding routine, with longer periods of sleep between feedings at night and more regular intervals during the day. This can provide parents with a greater sense of predictability and routine in their daily schedule.

More efficient feeding: As your baby’s digestive system matures, it may become more efficient at extracting nutrients from breast milk or formula. This can result in fewer instances of spit-up or reflux and a generally more settled feeding experience.

Interest in solid foods: Breast milk or formula remains the primary source of nutrition for babies at three months old. The World Health Organisation recommends exclusive breastfeeding for the first six months of life, with the introduction of solid foods around six months of age.

Responsive feeding: Pay close attention to your baby’s hunger cues and early signs and respond promptly to their feeding needs. Offering the breast or bottle when your baby shows signs of hunger, such as rooting or sucking on fists, helps establish a healthy feeding relationship and supports your baby’s nutritional needs.

More aware of their surroundings: 3-month-old babies are taking in more of the world, which might mean they get distracted during feeding. So feeding in public can be a trickier time for you both.

3-month-old sleep milestones

Sleep plays a crucial role in your baby’s growth and development, and by 3 months old, you may notice some significant changes in their sleep patterns and behaviours.

Longer nighttime sleep stretches: Many babies start to consolidate their nighttime sleep into longer stretches by 3 months old. While they may still wake up for feedings during the night, you may notice longer periods of uninterrupted sleep. You might even go six hours at a time without hearing your baby cry (yes, it’s possible).

Decreased nighttime feedings: As your baby’s stomach capacity increases and their nutritional needs are met more efficiently during the day, they may gradually reduce the number of nighttime feedings. Most babies may still wake up once or twice for feeding, while others may sleep through the night without needing to nurse or take a bottle.

Established bedtime routine: By 3 months old, you may have established a bedtime routine to help signal your baby that it’s time to wind down and prepare for sleep. This may include activities such as a warm bath, gentle massage, bedtime story, or lullabies – all of which can help your baby relax and transition to sleep more easily.

Improved self-soothing skills: As babies grow, they may become more adept at self-soothing and falling asleep independently. While some crying babies may still rely on rocking, nursing, or gentle patting to fall asleep, others may begin to develop self-soothing techniques, such as sucking on their fingers or a pacifier, to help them settle down.

More predictable nap schedule: By 3 months old, many babies start to establish a more predictable nap schedule, with regular nap times throughout the day. While individual nap lengths and frequency may vary, you may notice that your baby starts to take longer and more restorative naps, particularly if they are well-rested and not overtired.

Transition to longer sleep cycles: Babies at this age transition from shorter sleep cycles to longer ones, typically lasting between 60 to 90 minutes. This allows for deeper and more restorative sleep, promoting healthy growth and development.

Safe sleep environment: It’s essential to continue following safe sleep practices to reduce the risk of Sudden Infant Death Syndrome (SIDS) and other sleep-related accidents. Ensure your baby sleeps on their back in a crib or bassinet, even if they do a baby roll, with a firm mattress and no loose bedding, toys, or pillows. Keep the room at a comfortable temperature and avoid overheating.

Additional behaviours at 3 months

As your baby continues to grow and develop, you may notice additional behaviours emerging around the 3-month mark. These indicate their evolving cognitive, physical, and emotional abilities.

Fine motor skills
At 3 months old, your baby’s fine motor skills are beginning to develop, allowing them to engage in more intentional movements and interactions with their environment. Some common fine motor milestones at this age include:

  • Grasping objects: Your baby may start to reach for and grasp objects with greater purpose and coordination, using their hands to explore and manipulate toys, rattles, and other items within their reach.
  • Bringing hands together: You may notice your baby bringing their hands together midline, a significant milestone in hand-eye coordination and body awareness.
  • Exploring with hands and mouth: Babies are naturally curious and use their hands and mouths to explore objects and textures. Encourage safe exploration by providing age-appropriate toys and supervised playtime.

Development problem signs
While most babies develop at their own pace, it’s essential to be aware of any potential signs of developmental delays or concerns. Some red flags to watch for include.

  • Lack of eye contact: Limited eye contact or lack of response to visual stimuli may indicate potential vision problems or social communication delays.
  • Limited physical movement: If your baby shows little interest in moving or exploring their environment, including head movements, it could be a sign of developmental delay or motor skill issues.
  • Difficulty tracking objects: Babies should demonstrate the ability to visually track moving objects with their eyes by three months old. If your baby has difficulty tracking or shows no interest in visual stimuli, it may warrant further evaluation.

Emotional development
Emotional development is a critical aspect of your baby’s overall growth and well-being. By three months old, you may observe the following emotional milestones.

  • Social smiles: Your baby’s smiles become more intentional and responsive, particularly in response to familiar faces and interactions with caregivers.
  • Increased social interaction: Babies become more engaged and interactive with the people around them, showing signs of recognition and attachment to primary caregivers.

Emotional expressiveness: Your baby may display a wider range of emotions, including joy, excitement, frustration, and even sadness. Pay attention to their facial expressions and vocalisations as they communicate their feelings.

Development tips for your baby this month

At three months old, your baby is rapidly developing and becoming more interactive with their environment. Here are some tips to nurture their development.

Encourage interaction: Engage in frequent face-to-face interactions with your baby, talking, singing, and making eye contact. These interactions help strengthen the bond between you and support your baby’s social and emotional development.

Promote tummy time: Continue to incorporate tummy time into your baby’s daily routine to strengthen baby’s head, neck, shoulder, and arm muscles. Gradually increase the duration of tummy time sessions as your baby grows more accustomed to it.

Provide stimulating toys: Introduce age-appropriate toys that encourage exploration and sensory stimulation. Choose toys with different textures, colours, and sounds to engage your baby’s senses and promote cognitive development.

Read to your baby: Reading aloud to your baby is a wonderful way to promote language development and early literacy skills. Choose board books with bright, engaging illustrations and read to your baby regularly. It is one of the joys of raising children.

Establish routines: Consistent routines can provide structure and predictability for your baby, promoting a sense of security and stability. Establish regular feeding, sleeping, and playtime routines to help your baby feel more secure and comfortable.

Respond to cues: Pay close attention to your baby’s cues and signals, responding promptly to their needs for food, comfort, and affection. This responsive caregiving helps build trust and security in your relationship with your baby.

Provide gentle stimulation: Avoid overstimulation by providing calm, soothing environments for your baby to rest and play. Limit exposure to loud noises, bright lights, and overly stimulating activities, especially before bedtime.

Practice skin-to-skin contact: Skin-to-skin contact has numerous benefits for both you and your baby, including regulating your baby’s body temperature, promoting bonding, and reducing stress. Spend time cuddling and holding your baby skin-to-skin whenever possible.

Encourage exploration: Create safe opportunities for your baby to explore their surroundings and interact with objects. Allow them to reach, grasp, and manipulate toys and objects to enhance their motor skills and curiosity.

Seek support: Don’t hesitate to reach out to healthcare professionals, your baby’s doctor, parenting groups, or family members for support and guidance. Parenting can be challenging at times, and having a supportive network can make all the difference.

Items you will need this month

  • Nappies and wipes
  • Baby clothes (onesies, sleepers, socks, hats)
  • Feeding supplies (bottles, teats, formula, bottle brush)
  • Swaddle blankets
  • Baby monitor
  • Healthcare supplies (gentle soap, shampoo, lotion, baby brush or comb)
  • Baby toys
  • Nursing pillow
  • Burp cloths and bibs
  • Nappy bag for outings
  • Baby carrier

Checklist for this month

  • Schedule well-baby checkup
  • Monitor growth and development
  • Engage in interactive play
  • Practice safe sleep habits
  • Maintain feeding routine
  • Stay connected with support network
  • Prioritise self-care for yourself as a parent


Developmental Milestones: 3 Months, HealthyChildren.org. Available at: https://www.healthychildren.org/English/ages-stages/baby/Pages/Developmental-Milestones-3-Months.aspx

Your baby’s growth and development – 3 months old, Pregnancy, Birth, and Baby. Available at: https://www.pregnancybirthbaby.org.au/babys-growth-and-development-3-months-old

‘Your guide to the first 12 months’ (2023). Children’s Health Queensland. Available at: https://www.childrens.health.qld.gov.au/__data/assets/pdf_file/0033/174984/240201-Your-guide-to-the-first-12-months-1.pdf

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