Babies get hiccups because their diaphragm, the dome-shaped muscle beneath the lungs, contracts involuntarily and snaps the vocal cords shut, producing that familiar “hic” sound. This happens far more often in newborns and young infants than in older children or adults, and it’s almost always harmless. In fact, hiccups may actually serve a developmental purpose in the first months of life.
The Reflex Behind the “Hic”
A hiccup is a reflex, not a random muscle twitch. It follows a specific pathway through the nervous system. Signals travel along the phrenic nerve and vagus nerve to a cluster of nerve cells in the upper spinal cord, roughly between the third and fifth vertebrae of the neck. From there, a motor signal fires back out to the diaphragm, causing it to contract sharply. At nearly the same instant, the glottis (the opening between the vocal cords) slams shut. That sudden closure against the rush of incoming air is what creates the sound.
The reflex also involves the muscles between the ribs and briefly affects the tone of the esophagus and the valve at the top of the stomach. In babies, this entire loop is more easily triggered than in adults, largely because their nervous system is still maturing and the threshold for setting off the reflex is lower.
Hiccups May Help Babies Learn to Breathe
Researchers at University College London found that hiccups in newborns trigger a distinct pattern of brain activity: each diaphragm contraction produces two large brainwaves in the cortex, followed by a third. That third wave closely resembles what the brain generates in response to a sound, suggesting the baby’s brain is linking the “hic” noise it hears with the physical sensation of the diaphragm moving.
This process may be helping the brain build a map of the breathing muscles so that, over time, the baby can learn to control the diaphragm voluntarily. The same research group had previously found that babies kicking in the womb appear to create mental maps of their own bodies. Hiccups, which begin as early as the first trimester of pregnancy, may be doing the same thing for internal organs. In other words, every bout of hiccups is a small training session for the brain, reinforcing the connections between sensory input and muscle control.
What Triggers Hiccups in Babies
Even though hiccups serve a developmental role, specific situations make them more likely. The most common triggers relate to feeding and the digestive system:
- Swallowing air during feeding. Babies naturally gulp some air while breastfeeding or bottle-feeding, especially if they’re feeding quickly or crying beforehand. That extra air in the stomach can push against the diaphragm and set off the reflex.
- A full or distended stomach. Overfeeding or feeding too fast stretches the stomach wall, which sits right below the diaphragm. The pressure irritates the nerves that trigger hiccups.
- Feeding while upset. A baby who is extremely hungry or fussy before a feed tends to swallow more air and feed more frantically, making hiccups more likely during or after the meal.
- Sudden temperature changes. A shift in environmental temperature, like being undressed for a bath or moved from a warm room to a cooler one, can provoke the reflex.
Gastroesophageal reflux (when stomach contents flow back up into the esophagus) can also irritate the nerves involved in the hiccup reflex. Pediatric gastroenterology guidelines list hiccups as one of the symptoms assessed when evaluating an infant for reflux disease. On its own, though, hiccupping is not enough to diagnose reflux. No single symptom or combination of symptoms reliably confirms reflux disease in infants and toddlers.
How Long They Last and When They Fade
A typical bout of hiccups in a baby lasts anywhere from a few minutes to about 10 minutes. Some episodes stretch a bit longer, but most resolve on their own without any intervention. Newborns may hiccup several times a day, which can feel alarming but is completely normal.
The frequency tends to decrease as the baby’s nervous system matures. Most parents notice a significant drop-off by the time their baby is 6 to 12 months old. Occasional hiccups continue throughout childhood and into adulthood, of course, but they become far less frequent and less easily triggered.
What Actually Helps
If hiccups start during a feeding, pause and change your baby’s position. Try to get a burp out, or simply hold the baby upright and let them relax for a moment. If the hiccups don’t stop within 5 to 10 minutes, resuming the feeding for a few minutes often does the trick, as the sucking and swallowing rhythm can help reset the diaphragm.
Prevention is more reliable than intervention. Feeding your baby before they become extremely hungry and fussy reduces the chance of frantic feeding and excess air swallowing. Keeping feeds calm and paced, with burping breaks partway through, makes hiccups less frequent over time.
Folk Remedies to Avoid
Many traditional hiccup remedies that work (or seem to) for adults are unsafe for babies. Startling them, pulling their tongue, giving them water to sip while tipped backward, or pressing on their fontanelle have no scientific basis and can genuinely distress or harm an infant. Gripe water, a popular over-the-counter remedy, lacks strong evidence for hiccups and is generally not recommended for babies under 6 months. The safest approach is patience: hiccups bother parents far more than they bother the baby.
When Hiccups Signal Something Else
Hiccups alone are rarely a sign of a medical problem. But if your baby hiccups persistently throughout the day, seems uncomfortable or irritable during episodes, spits up frequently, arches their back during or after feeds, or isn’t gaining weight well, those combined patterns could point to gastroesophageal reflux disease or another digestive issue worth investigating. The key distinction is the cluster of symptoms, not the hiccups in isolation. Reflux symptoms in infants are nonspecific, meaning they overlap with many other conditions, so a pediatrician’s evaluation is the only way to sort it out.