This is Why Some Newborn Babies Turn Half-Red

Illustration for article titled This is Why Some Newborn Babies Turn Half-Red

One out of every ten newborn infants displays a weird quirk of the human body called “harlequin sign.” It makes babies spontaneously turn parti-colored, especially when their tiny bodies heat up.

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Harlequin sign begins freaking parents out at two days after the child’s birth. When the parents, for a moment, lay their baby on his or her side, half of their kid turns bright red. And when we say half, we mean exactly half. One of the features of harlequin sign is it neatly bisects the body along a straight line.

Illustration for article titled This is Why Some Newborn Babies Turn Half-Red

Meanwhile, the side of the body that doesn’t go red is extremely pale, as if a new baby were intentionally trying to make the color difference as terrifying as possible for its nervous parents. The color change dissipates fairly quickly. If parents are lucky it goes away after half a minute, but it can last as long twenty minutes, at which point, many panicked parents will be clawing at the doors of the emergency room.

Newborn blood vessels are highly sensitive to even slight changes in temperature or body position (or even mood), constricting or expanding with a corresponding change in blood flow. In newborns prone to Harlequin sign, this manifests as a color change in the skin.

Occasionally this syndrome does occur with complications, but most babies with harlequin sign—including the baby girl pictured above—have a bad case of the absolutely fines. Eventually the sign goes away on its own.

At least that’s the case with newborns. Older children, and stroke victims, sometimes develop harlequin sign as a result of Horner’s syndrome—the disruption of the nerve pathways to one side of the face. Because this disruption isn’t restricted to the skin, people with this sign also have one eyelid that droops a little, and one pupil that doesn’t respond to light the way the other one does. Although it can be embarrassing, the syndrome isn’t painful or debilitating, and clears up when the nerve disruption itself is treated or heals.

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Infant Image: NBCI

DISCUSSION

BlackMarketChimp
BlackMarketChimp

Isn’t the human body strangely complicated? After my mom had back surgery she developed this thing where if she pressed her skin at all it would swell up in that area. She could write on herself with a finger and in a minute it would puff up and you could actually read it. It had pretty good resolution too if you used a pen or something, no pain or irritation, just weird. She thought about doing some stigmata stuff to freak out my uber Christian uncle and aunt, but I convinced her that might not be the best idea (my aunt is stupid enough to have really taken it seriously).

Eventually it went away, but we never did figure out what the cause was (possibly some random side effect of medication after surgery).