The Growing Child: 1 to 3 Months

1 to 3 month old baby playing with feet while laying on her back.

How much will my baby grow? 

While all babies may grow at a different rate, the following is the average for boys and girls 1 to 3 months of age:

  • Weight: average gain of about 1½ to 2 pounds each month

  • Height: average growth of over 1 inch each month

  • Head size: average growth of about ½ inch each month

What can my baby do at this age?

As your baby begins to grow, you will notice new and exciting abilities that develop. Babies at this age begin to relax the tight muscle tone of newborns and start extending their arms and legs more. Babies may progress at different rates, but the following are some of the common milestones your baby may reach in this age group:

  • Some of the newborn protective reflexes start to disappear

  • Neck muscles become stronger, head bobs then is held erect

  • Turns head from side to side when placed on belly

  • Brings hands or objects to mouth

  • Looks at hands

  • Follows light, faces, objects

  • Listens to sounds

  • Opens and closes hands

  • Holds, then drops a rattle or other object

  • Active leg movements

  • At the end of 3 months:

    • Raises head and chest when placed on belly

    • Starts to reach hands to objects, may bat at hanging object with hands

What can my baby say?

It's very exciting for parents to watch their babies become social beings that can interact with others. Every baby develops speech at his or her own rate, but these are some of the common milestones in this age group:

  • Starts to imitate some sounds (coos, vowel sounds)

  • Cries become more purposeful and are different for hunger, fatigue, and other needs

What does my baby understand?

A baby's understanding and awareness of the world around him or her increases during this time. Babies may progress at different rates, but these are some of the common milestones in this age group:

  • Knows familiar voices, especially of mother and father

  • Smiles in response to others

  • Responds to social contact, may coo

  • Moves arms, legs, body in rhythm with other's voice

How to help increase your baby's development and emotional security

Young babies need the security of a parent's arms, and they understand the reassurance and comfort of your voice, tone, and emotions. Consider the following as ways to foster emotional security of your newborn:

  • Hold your baby face to face and make eye contact.

  • Talk to your baby with a soothing, animated voice throughout the day while dressing, bathing, feeding, or playing with your baby.

  • Sing to your baby.

  • Give your baby rattles and soft toys with different sounds.

  • Let your baby hear different sounds (for example, wind chime, ticking clock, soft music, or music box).

  • Show your baby bright pictures of black and white images.

  • Hang a mobile with bright objects above your baby.

  • Call your baby by name.

  • Hold your baby during feedings and provide comfort when he or she is distressed and cuddling when happy.

Online Medical Reviewer: Donna Freeborn PhD CNM FNP
Online Medical Reviewer: Heather Trevino
Online Medical Reviewer: Liora C Adler MD
Date Last Reviewed: 12/1/2018
© 2000-2021 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.