Why Your Baby Might Be Stuck in Fight-or-Flight.
A newborn's nervous system isn't a blank slate. By the time a baby arrives in the world, it has already been shaped by nine months of connection to their mother's physiology, and it's about to be shaped again — profoundly — by the process of being born. For some babies, that shaping happens smoothly. For others, a combination of prenatal, birth, and postnatal experiences can leave their nervous system stuck in a state of protection rather than one of calm, connected safety.
This isn't about blame or "what went wrong." It's about understanding what's happening underneath the surface when a baby seems unsettled, and why a nervous-system lens can offer families some real answers.
It Starts Before Birth
A developing baby is in constant physiological conversation with their mother. Maternal stress hormones cross the placenta, and a mother's own nervous system state — calm and regulated, or chronically activated — becomes part of the environment her baby is growing in. This is co-regulation beginning before a single breath is taken. It doesn't mean a stressful pregnancy guarantees a dysregulated baby, but it does mean the nervous system's very first experiences of the world happen in utero, long before labour begins.
Birth Is the Biggest Nervous System Event of a Baby's Life So Far
Birth asks an enormous amount of a baby's still-forming nervous system, particularly around the upper neck and brainstem — the exact region where the vagus nerve, the body's main highway for regulation and calm, does much of its work.
Position matters. A baby who spent the final weeks or the labour itself in a posterior or otherwise less-than-optimal position may experience more mechanical stress through the neck and upper spine as they navigate the birth canal.
Caesarean birth removes the rhythmic, sequential compression a baby typically experiences moving through the birth canal, and often comes with its own layer of stress — whether planned or, particularly, unplanned or urgent.
Forceps or vacuum-assisted delivery apply direct mechanical force to the head and upper neck, an area rich in the nerve pathways responsible for feeding, digestion, and nervous system regulation.
None of these experiences are "bad" in isolation — many babies move through all of them and settle beautifully. But they are inputs, and for some babies, they add up.
The Window After Birth Matters Too
The period immediately following birth is a critical co-regulation window. This is when a baby's nervous system is looking to their mother — through touch, smell, voice, and skin-to-skin contact — to help downshift out of the intensity of being born and into a state of calm.
Medication exposure, whether to mother or baby during labour and birth, can influence how alert and available a baby is for this early bonding and regulation.
Separation — even short periods apart for medical monitoring, NICU care, or routine hospital procedure — interrupts this window at exactly the moment a baby's nervous system needs consistent co-regulatory input the most.
What a Nervous System Stuck in Fight-or-Flight Can Look Like
When these prenatal, birth, and postnatal stressors stack up without enough co-regulation to balance them, some babies' nervous systems can get stuck in a sympathetic, "fight-or-flight" pattern rather than moving fluidly into calm, connected states. In everyday life, this may show up as:
Difficulty settling
Difficulty staying asleep, or waking frequently and hard to resettle
Being easily startled or rattled by small changes
Difficulty latching well at the breast or bottle
Digestive upset — gassiness, reflux-type symptoms, unsettled feeds
High muscle tone and arching through the back and neck
A strong preference for turning the head to one side
Each of these can be understood as a nervous system working hard to protect itself. High tone and arching often reflect ongoing muscular guarding from a system that hasn't found "off." A head turning preference frequently points to tension or restricted movement through the upper neck, an area intimately connected to birth mechanics and vagal function. Settling and sleep difficulties, and a jumpy startle response, are classic signs of a nervous system sitting in sympathetic activation rather than the calm, ventral state where rest and digestion happen easily.
Where This Leaves Families
Understanding these signs through a nervous-system lens can be a relief for parents who have been told their baby is simply "difficult" or will "grow out of it." It reframes the picture: this is a nervous system that has been through a lot, and may need some extra support finding its way back to safety and regulation.
Gentle, neurologically focused chiropractic care is one part of this picture. A careful assessment can identify areas of tension and restriction related to birth mechanics, particularly through the upper neck, and offer the nervous system an opportunity to release that guarding and settle into calmer patterns. Alongside this, ongoing co-regulation from parents — skin-to-skin contact, a calm nervous system nearby, consistent and predictable care — continues to give a baby's own nervous system the cues it needs to feel safe.
If this sounds like your baby, you're not imagining it, and you're not alone. Understanding what's happening underneath the surface is often the first step toward things feeling easier for the whole family.