"Why is my newborn fighting sleep?"
- Lindsay Sinopoli - CCSC, CLC, NCS
- Jun 2
- 6 min read
Updated: Jun 2
If you're reading this while desperately trying to settle your fussy baby who seems determined to stay awake, you're not alone! Many parents are caught off guard when their peaceful newborn suddenly starts fighting sleep around 4-6 weeks old.
The good news? This is completely normal! And understanding the science behind it can help you navigate this challenging phase.

The "Newborn Coma" Comes to an End
During the first few weeks of life, most babies seem to sleep constantly—what we lovingly call the "newborn coma." This isn't just exhaustion from being born; there's actual science behind this sleepy phase.
Your baby was born with a large maternal dose of melatonin (your sleep hormone) still circulating in their system. This borrowed melatonin keeps them naturally drowsy and helps them sleep easily almost anywhere, anytime.
But here's where things get tricky: this maternal melatonin begins wearing off around 4-6 weeks old, right when your baby is becoming more alert and aware of their surroundings. Suddenly, the world becomes a much more stimulating place, and without that natural sleep aid, falling asleep becomes genuinely challenging for them.
If your baby receives too much stimulation during the day—bright lights, lots of visitors, loud sounds, or excessive handling being passed around, their developing nervous system can become overwhelmed and "shut down" as a protective mechanism.
The Melatonin Gap: Why Sleep Gets Harder
While your baby loses their borrowed melatonin around 4-6 weeks, they don't begin producing their own melatonin until 8-12 weeks old. This creates what I call the "melatonin gap"—a period where your baby has little to no natural sleep hormone to help them drift off peacefully.
Even once babies start producing their own melatonin, they don't begin to properly regulate their sleep hormones until around 4 months old. This means those first few months require extra patience and support as your baby's sleep system gradually matures.
Day/Night Confusion: When Babies Get Their Wires Crossed
One of the most frustrating challenges for parents of newborns (0-4 weeks) is day/night confusion...
Here's what happens: if your baby receives too much stimulation during the day - bright lights, lots of visitors, loud sounds, or excessive handling being passed around -their developing nervous system can become overwhelmed and "shut down" as a protective mechanism.
When babies shut down from overstimulation, they often sleep for unusually long stretches during the day (sometimes 4-6 hours at a time). While this might seem like a blessing, it creates a problematic cycle. These marathon daytime sleeps mean your baby isn't tired when nighttime arrives. Instead, they flip their schedule and seek awake time at night when the environment is naturally calmer and less stimulating.
This day/night confusion is particularly common in the first month of life when babies haven't yet developed their circadian rhythms. The key is creating gentle boundaries between day and night from the very beginning, even during the "newborn coma" phase.
Overstimulation: The Hidden Sleep Thief
As your newborn becomes more alert, they're also becoming more susceptible to overstimulation. Their developing nervous system can easily become overwhelmed by lights, sounds, textures, and even too much interaction. When babies get overstimulated, their bodies release stress hormones like cortisol and adrenaline—the exact opposite of what they need to fall asleep peacefully.
Signs your baby might be overstimulated include:
Crying that seems inconsolable
Arching their back or turning away from stimulation
Clenched fists or jerky movements
Fighting sleep even when clearly tired
Sleeping for unusually long stretches during the day, then being wide awake at night
Soothing Strategies That Actually Work
The 5 S's: Your Newborn's Comfort Toolkit
Dr. Harvey Karp's famous "5 S's" are incredibly effective for calming fussy newborns and preparing them for sleep:
Swaddling: Wrapping baby snugly mimics the womb's security
Side/Stomach Position: Hold baby on their side or stomach (never for sleep—always back to sleep)
Shushing: Loud shushing sounds replicate the whooshing sounds of the womb (if your baby is crying, try to match their volume - the louder the better! Then reduce your volume as they settle)
Swinging: Gentle, rhythmic motion soothes the nervous system
Sucking: Pacifier or clean finger activates the calming reflex
These techniques work because they recreate the familiar sensations of the womb, helping your baby feel secure and ready for rest.
Red Light Therapy: Your Secret Weapon
One of my favorite tools for helping newborns settle is red light therapy using devices like the Hatch Rest Light. Here's the science: the red/orange hues mimic a sunset, signaling to your baby's brain that nighttime is approaching and it's time to prepare for sleep.
Key tip: Place the red light on the floor! The lower half of our eyes detect and process orange and red hues, interpreting them as the setting sun and naturally boosting melatonin production. This works even for young babies whose sleep hormone production is still developing.
Mastering the Bassinet Transfer
The dreaded bassinet transfer—where your peacefully sleeping baby suddenly wakes the moment they touch the mattress—is one of the biggest challenges new parents face. Here's how to master it:
Before the transfer:
Sleep with baby's spare crib sheets (for 1-2 nights) in your bed to transfer your comforting scent, before using it in baby's sleep space
Spend skin-to-skin time before sleep attempts
Warm the bassinet with a heating pad (remove before placing baby down)
During the transfer:
Move slowly - quick movements trigger the startle reflex
Keep one hand on baby's chest once you lower them down
Don't lift your hands away immediately; maintain contact for 30-60 seconds
If baby startles, spend time soothing in the crib/bassinet with your voice and gentle touch, until they settle (holding them in the side lying position is a great tool here! Just remember to slowly roll baby onto their back before leaving)
The key insight: Don't overthink when to put them down. After your soothing pre-sleep routine, aim to place baby in the bassinet before their eyes close completely. Yes, they may startle initially, but you can stay with them as long as they need to soothe in their sleep space, before leaving the room.
Falling asleep with you cribside, while lying in and falling asleep in their sleep space, will better assure a lovely long stretch of sleep!
Preventing Day/Night Confusion
During the day: Keep environment bright and engaging during wake periods, but watch for overstimulation cues and dial it down if you notice baby becoming overly fussy, or routinely "shutting down"
Natural light with curtains partially drawn is a good way to gently incorporate daylight exposure for easily overstimulated babies
During the night: Keep lights dim (ideally red if you need light during night feeds and changes), interactions minimal, and environment calm
Limit daytime sleep stretches: If baby sleeps longer than 3 hours during the day, gently wake them for a feed
Create contrast: Make nighttime feeds quiet and boring, daytime feeds social and bright
Don't always believe the old school advice!
Babies learn daytime/nighttime distinction from gentle exposure to daylight and activity during awake time, not during sleep time. Bright lights and chaos during sleep will not help them learn the difference between daytime and nighttime, but it will likely perpetuate the issue...
Create a Calming Environment
Dim all other lights (besides red light) for 10-20 minutes before sleep time
Use white noise to buffer sudden sounds
Keep the room comfortably cool (68-70°F)
Make the room "boring"—minimal stimulation helps prevent overstimulation
Watch for Early Sleep Cues
Newborns have very short wake windows—often just 45-90 minutes. Look for early signs of tiredness:
Glassy eyes
Rubbing eyes or ears
Becoming less engaged
Slight fussiness
Remember: This Phase Is Temporary
While it might feel endless when you're in the thick of it, this challenging sleep period is temporary. Most babies begin to settle into more predictable patterns once their own melatonin production kicks in around 8-12 weeks, with significant improvement by 16 weeks when sleep hormone regulation begins.
Your baby isn't fighting sleep to be difficult—their little system is simply learning how to navigate the world without the sleep aids they were born with. With patience, consistency, and the right environment, you can help them through this transition!
If you're struggling with persistent sleep challenges beyond the newborn stage, I've got your back Mama! Every baby deserves restful sleep, and every parent deserves the peace of mind that comes with it.
Sweet dreams are coming - I promise.
Lindsay Sinopoli is a Mom of 3, 6x Certified Sleep Consultant and founder of Jolly Good Sleep, serving families in Charlotte, NC and beyond. With over 100 families sleep transformed, she specializes in gentle, attachment-based sleep solutions that honor your family's unique needs.