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Weird newborn
things you can
safely ignore

For first-time parents spooked at 3 a.m.
No. 269Pregnancy & KidsPart 41 of 42Fact-checked Oct 15, 2026
Video2:11 · English voice (AI) · English subtitles

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The full narration of the video.

A baby boy, three days old, and his chest is swelling. You're changing him at midnight, feel two little lumps, and want to rush to the hospital. Hold on. Lots of newborn quirks look scary, but need nothing from you.

Think of your baby as a brand-new home, just handed over. The utilities just came on, so pipes knock and lights flicker; and the last owner left a few things behind. Those two lumps are what got left behind.

During pregnancy, the mother's estrogen, a hormone, crossed the placenta into the baby. Boys and girls alike: the chest puffs up, and some even leak a few drops of milk. A baby girl may even show a little blood in her diaper, like a tiny period.

Once mom's hormones clear out, it all fades on its own in two weeks to two months. Your only job: don't squeeze. Grandparents may say you should, but squeezing can cause an infection. Now the knocking pipes. Baby's parts just started working on their own, so there's noise.

After a feed, hiccup after hiccup. That's a thin sheet of muscle between chest and belly, twitching. It's called the diaphragm. It doesn't hurt or bother the baby, and it stops by itself. Sneezing isn't a cold either: the nose is tiny, dust and milk get in, and a sneeze sweeps it clean.

And the flickering lights? Mid-sleep, both arms suddenly fling out, as if startled. That's the built-in startle reflex. It fades by three or four months. There's something left in the mouth too: tiny white dots on the gums that grandparents call "horse teeth."

They aren't teeth, just little bits of leftover skin, gone in weeks to months. Never pick them with a needle or rub them with cloth. Break the skin, and germs get in. Still, a few noises in this new home can't wait.

Asleep, a baby may take a few quick breaths, pause five to ten seconds, then go on. That's periodic breathing, and it's normal. But a pause over twenty seconds, or lips turning blue: call an ambulance right away. Yellow skin comes in two kinds. About six in ten babies turn yellow on day two or three, clearing in about two weeks. Yellow on day one means the hospital, that same day.

And under three months old, a temperature of thirty-eight Celsius means don't wait at home. Most newborn quirks are a new home settling in, not illness. When unsure, ask your pediatrician. Of these, which one did you think was a sickness?

1

A brand-new home,
just handed over

LOOKS LIKE
Something is wrong with the baby
ACTUALLY
The water and power just came on,
and things are settling in
Pipes knock, lights flicker, and the previous owner left a few things behind. Most of it sorts itself out in a few weeks.

A baby's body parts have only just started working on their own, so there are noises. And what mom passed on during pregnancy hasn't fully cleared yet. The seven things below are all like that. The last three are the exceptions.

2

The chest bumps
came from mom

During pregnancy, mom's estrogen (a hormone) crosses the placenta into the baby. After birth, it takes a while to clear out.

Swollen chestBoys and girls both get it; some leak a few drops of milk
A little blood in the diaperA baby girl's "mini period", sometimes with white discharge

It fades on its own
in 2 weeks to 2 months.

Your only job: don't squeeze. Some grandparents say squeezing helps, but it can cause an infection. If it turns red, feels hot or keeps growing, see a doctor.

3

Knocking pipes:
hiccups and sneezes

diaphragm

Hiccup after hiccup after a feed? That's the thin muscle between the chest and belly twitching. It's called the diaphragm. It doesn't hurt the baby. No water, no startling him. It stops by itself.

Sneezing doesn't mean a cold either. The nose is tiny; dust and milk get in, and one sneeze sweeps them out. If it goes on with coughing, trouble breathing or poor feeding, call a doctor.

4

Flickering lights:
arms flung out in sleep

Mid-sleep, the baby suddenly flings both arms out, as if startled. This is the built-in startle reflex, which doctors call the Moro reflex. It's strongest in the first month and fades by 3 to 4 months.

Two more are common. In sleep, a few quick breaths, a 5 to 10 second pause, then breathing again: that's periodic breathing. Eyes that sometimes cross are also normal before 4 months (why newborn eyes look a bit odd).

5

Little white dots
on the gums

In China, grandparents call them "horse teeth". Doctors call them Epstein pearls. They aren't teeth, just tiny bits of leftover skin. 60 to 80 percent of newborns have them. They don't affect feeding and go away in weeks to months.

Never pick them with a needle
or rub them with a cloth.

A break in the mouth lets germs in. White patches that wipe off, plus a baby who won't feed, may be thrush. See a doctor.

6

These three
can't wait

Breathing stops for 20+ seconds,
or lips turn blue
Call emergency services right away (120 in China).
Yellow on
day one
Go to the hospital that day. About 6 in 10 babies turn yellow on day 2 or 3 and clear in about two weeks; that kind is usually fine. Still yellow after two weeks? Get it checked too.
Under 3 months,
temperature hits 38°C
Don't wait at home. Go to the hospital.
Mostly a new home settling in,
not illness
When in doubt, ask a pediatrician.
Which of these did you
think was an illness?
Samshang × Maddox
Sources: U.S. National Library of Medicine MedlinePlus, Hormonal effects in newborns; UW Medicine newborn handbook, Getting to Know Your Baby's Body; StayWell, Stuffy Nose, Sneezing, and Hiccups in Newborns; MedlinePlus and pediatric clinic guides on periodic breathing and apnea; WebMD, Moro reflex; Healthline and WebMD, Epstein pearls; DXY (Chinese medical site), newborn gum cysts; NHS Cambridge University Hospitals and NHS England, newborn jaundice; American Academy of Pediatrics, fever in babies under 3 months
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