by Harvey Karp, MD, FAAP

Infant crying is a fact of life. It’s one of the important ways newborns communicate their needs to us. Fortunately, most of the time even a baby’s passionate shrieks just mean he’s hungry, wet, soiled, or lonely, and he will melt into blissful quiet once you give him what he needs.

In fact, we call babies “infants” exactly because they can’t tell us what’s on their little minds; the word infant comes from ancient Latin and means “without a voice.” Most babies’ bouts of the fussies only last for a few minutes, totaling less than an hour a day. However, as many parents can attest, some babies have huge voices and the energy to cry loudly for a long time!

What if your cute little guy keeps blasting even though you think you have watched his every sign and given him a good feeding, put on a dry diaper, and is being cuddled in your arms? What happens if you try everything and he still doesn’t stop screaming? That’s when parents start to wonder if this is more than just fussiness—if it may in fact be the mysterious condition called colic, or persistent crying.

How do You Know if Your Baby has Colic?

Infants with colic flail and kick and let out frantic screams. Once they get started, they can yell, on and off, for hours, often mysteriously starting at just about the same time every day—creating a family’s very own “witching hour.”

It is estimated that 10-15% of all babies suffer from colicky crying. Doctors define colic by the “rule of threes,” which states that a baby has colic if he cries at least: 3 hours a day, 3 days a week, for 3 weeks in a row. That’s a lot of crying—and that doesn’t include your shrieks!

What Causes Colic in Babies?

For centuries, doctors and grandmothers alike have argued about the cause of this marathon crying. Some swear it’s caused by gas, overfeeding, acid reflux, or anxiety. Some even think it’s from an “evil eye.” Recently, there’s been discussion that some babies cry because they need to eat more “good bacteria” or so-called probiotics, like those found in yogurt.

But none of these can really be the cause of infant crying. How can I be so sure? Because of several well-known facts:

* X-rays of fussy babies show they have almost no gas trapped in their stomachs when they’re crying. In fact, since they swallow air while crying, babies’ tummies are usually filled with much more air an hour after their crying fit is over even though they are, by that time, totally calm and comfortable.
* In some African cultures, colic is extremely rare (even though those babies are nursed 50-100 times a day!)
* Most fussy babies calm down whe