You asked

Why is my baby crying?

When baby cries, the first thought usually is that the baby is hungry. If you learn the signs of hunger, you will be able to start the feeding before the baby reaches the crying stage. Some of the tell tale signs in newborns are: fussing, smacking of the lips, rooting and putting their hands to their mouth.

The “I'm in pain” cry is the sound a baby makes when they get their vaccinations. For most babies, this is a high-pitched cry. It is a clear distress call and is something you remember vividly.
The “I'm tired” cry is much more subtle, so it becomes important to watch for visible clues of tiredness.
Common signs include rubbing of the eyes, yawning, pulling on the ears, nose or hair, clinging, and suddenly becoming hyperactive. By the time baby shows these signs, they are already to the point of being overtired.

Some babies will let you know straight away when they need a nappy change. Others can tolerate a dirty nappy for a long time. In either case, it is easy to check and simple to cure.

Stomach woes associated with gas or colic can result in a lot of crying. The mysterious condition called colic is defined as an inconsolable crying that lasts for at least three hours a day, for at least three days a week, and goes for at least three weeks in a row. If baby fusses often and cries right after a feed, they may be experiencing some sort stomach discomfort. Whether they are breastfeed or suck from a bottle, all babies swallow air. Burping a baby is not mandatory, but if baby cries after a feeding, perhaps all they really need is a good burp. 

Teething can be painful. Some suffer more than others, but all babies are likely to be fussy and tearful at some point during teething. The first tooth usually breaks through sometime between four and seven months, but it can happen earlier.

Crying can be a baby's way of saying, "I've had enough." Babies learn from the stimulation in the world around them. Sometimes they have a difficulty processing it all (over stimulation). To manage baby's sensory overload, try removing the baby to a quiet place and allowing baby to rest.

Demanding babies are eager to see and experience the world. And often the only way to stop the crying and fussing is to remain active. Try putting the baby in a sling, front carrier or backpack. Plan lots of activities such as visiting with other parents with babies, outings to the park, children's museum or the zoo.

If baby’s basic needs have been met and you've comforted them but they are still crying, they may be getting sick. Be alert for signs of illness. You may want to check their temperature to see if they have a fever. The cry of a sick baby is distinct from one caused by hunger or frustration.

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