First-Month Milestones: What Your Baby Can Do, and the Signs to Tell the Doctor at Checkups

Your baby’s first month goes by so fast. Your days are all feeding, changing diapers and rocking to sleep, until sometimes you wonder: besides eating and sleeping, what can my baby actually do? And is this normal? Scroll past a friend’s baby on social media who seems more “advanced”, and your heart sinks a little.

So we’ve gathered what most babies from birth to 1 month can do, from the DSPM manual that Thai hospitals use and from AAP information, along with the signs to note down and tell the doctor at your checkup. But first: every baby develops at their own pace. This list is for observing, not a test.

Before you read: why many Western checklists start at 2 months

Quick Answer: Because the US CDC revised its checklists to start at 2 months, using the standard that “most children, 75% or more, can do this by this age.” In Thailand, the DSPM manual (the Developmental Surveillance and Promotion Manual) has checks for birth to 1 month.

Simply put, if your baby can’t do some items yet, it doesn’t immediately mean something is wrong. It’s just something to mention to the doctor so it can be followed up. The pink book (สมุดสีชมพู, the Thai Mother and Child Health Handbook) also has pages for recording age-based development, which the nurse helps assess.

1. What can your baby see?

Quick Answer: They see clearly up close, at about 20 to 30 centimeters. They love faces most of all, and like black and white or high-contrast patterns.

• 20 to 30 centimeters is about the distance from your chest to your face while feeding
• The DSPM manual asks you to watch whether your baby can follow an object to the middle of their body when you slowly move something brightly colored in front of them

2. How does your baby hear and respond to sound?

Quick Answer: AAP says a baby’s hearing is fully developed. Your baby will startle or move when they hear loud sounds or voices, and may turn toward familiar voices.

The DSPM manual uses “startles or moves the body when hearing speech at a normal level” as its check for this age. Many hospitals screen newborns’ hearing before they go home. If you’re not sure whether your baby was tested, or the result said to retest, write it down and ask at your next appointment.

3. What kind of movement is normal?

Quick Answer: Movements are still jerky, not smooth. Your baby can bring their hands near their eyes and mouth, and turn their head to one side when on their tummy, but can’t hold their head up yet.

• AAP explains that 1-month-old babies move their arms in jerky, trembling ways, and their head flops backward if not supported
• The DSPM manual asks you to check that when lying on their tummy, your baby lifts their head and turns it to one side
• Something to quietly watch for: your baby moves both arms and legs about equally, not one side staying still all the time

Tummy time, letting your baby lie on their tummy while awake with someone watching, helps build neck muscles from the first day home. How to do it safely is in 5 things you can play with your baby every day.

4. How does your baby communicate with you?

Quick Answer: Besides crying, your baby starts making cooing sounds and can gaze at your face briefly, for about 1 to 2 seconds, according to the DSPM manual.

At this stage crying is still your baby’s main language. Hungry, sleepy, wet diaper, wants to be held: it’s all crying. The easiest way to “chat” is to copy your baby’s cooing sounds back to them, then wait for them to answer, just like a real conversation.

5. Is your 1-month-old smiling at you yet?

Quick Answer: Mostly not yet. Smiles in the first month are usually reflex smiles during sleep. A smile your baby means as a response to you usually comes at about 6 to 8 weeks.

CDC lists smiling back as a 2-month milestone. If your 1-month-old isn’t smiling back yet, don’t worry. Read how to tell a real smile from a sleep smile in Baby’s first real smile: when does it come?

6. If your baby was born early, how do you track milestones?

Quick Answer: Go by corrected age, which is the actual age minus the number of weeks born early. Use it for the first 2 years.

For example, if your baby was born at 36 weeks (4 weeks early), at an actual age of 1 month they may still be developing like a newborn, which is normal for them. If you change hospitals, always tell the doctor how many weeks your baby was born at.

7. Signs to tell the doctor at your checkup

Quick Answer: If your baby has trouble feeding, doesn’t react to loud sounds, doesn’t follow moving objects, or is stiff and barely moves their arms and legs, tell the doctor. Mayo Clinic lists these as signs to discuss in the first 3 months.

Also note these down to ask about:

• One arm or leg clearly moving less than the other
• Unusually floppy, or often stiff and tense
• Never startling at sounds, or a hearing test result that said to retest
• Hardly ever looking at faces, even up close
• Anything that feels “not right” to you, even if you can’t explain it. The feelings of the person with the baby all day are important information

Go to the hospital right away if…

These aren’t about development. They’re signs of illness that can’t wait for an appointment.

• Fever of 38°C or higher in a baby under 3 months
• Drowsy, hard to wake, or refusing to feed
• Breathing fast, trouble breathing, or turning blue
• Seizures, or stiffening and jerking on and off
• Jaundice (yellow skin) getting worse

See more details in A guide to your baby’s first 3 months.

How to support first-month development without buying anything

Quick Answer: Hold, cuddle, make eye contact, talk, sing, and give supervised tummy time while awake. That’s all this age needs.

Mayo Clinic recommends making eye contact when your baby looks at you, talking to your baby with changing facial expressions and tone of voice, reading and singing, and says skin-to-skin contact helps your baby’s brain development. The next checkup usually comes with the 2-month vaccines, so bring the checklist above along with the pink book.

The first month isn’t measured by how quickly your baby can do things. It’s measured by your baby knowing someone who loves them is right there. And on that one, you’ve already got everything covered.