Increased crying among healthy infants in the Western world is now recognized in all infants in the first few weeks of life. This includes crying for prolonged periods of time for no discernable reason, a characteristic almost unique to the first few months of life. In fact, it isn’t unusual for a normal infant to cry from one to five hours daily, with a peak during the first two months of life.

In less than 5% of these infants is there ever evidence of organic disease to help explain increased crying behaviour. Furthermore, prolonged crying takes place despite excellent parental care. Fortunately, after the age of five months, the increased prolonged periods of inconsolable crying decrease, crying becomes more intentional, and is more related to events in the environment.

However, persistent crying, especially when associated with sleeping and feeding problems that continue beyond four months, often in the context of multiple parental psychosocial risk factors, can be a predictor of poor infant social and emotional development.

What do we know?

All infants cry, but most of the crying is unexplained. The explanations often attributed to infant crying include pain, hunger, anger and boredom. Unexplained increased excessive crying within the first three months of life that occurs in otherwise healthy infants is often labelled “infant colic.” Depending on how it is defined, colic is said to affect about 10 to 20% of babies at this age. One salient characteristic is that it tends to follow a pattern of increasing for the first two months of life, peaking at about six weeks, and usually lessening by the fourth or fifth month of age. However, this pattern is true of all infants, whether their crying is considered “excessive” or not, and is now recognized as the “normal crying curve.”  During this period, intense crying bouts can occur with no apparent reason, are difficult to soothe, and often last 35 to 40 minutes on average or as long as a couple of hours. They usually occur in the late afternoon or evening.

Infants whose fussiness persists throughout infancy, or whose increased fussiness gets worse after the first four months, are often said to have a difficult temperament. Crying related to infant colic can be hard to distinguish from crying related to difficult temperament. The major difference is that in colic, the crying bouts lessen with time, while in infants with temperamental difficulties, the increased fussing lasts throughout infancy, and even beyond. Though crying due to difficult temperament can sometimes be modified, difficult temperament is often stable across the life span, constitutionally based and heritable.

Positive consequences:

Excessive crying through the first months of life can cause frustration and stress within the family. Nevertheless, there are positive consequences associated with crying behaviour. One such consequence is that crying allows infants to build close relationships to those who most reliably respond to their needs. In this way, crying may be central to the formation of an emotional bond or “attachment” with a particular caregiver(s).

Negative consequences:

Many studies on colicky infants have shown convincingly that there are no negative long-term outcomes for the infants. Most parents show no negative consequences, but lack of confidence in caregiving abilities persists in some, and they are more likely to consider their infants “vulnerable.”  However, infants with difficult temperament are more likely to experience long-term differences. Infants who are fussy and difficult to soothe are more likely to be at increased risk for preschool problem behaviour, adolescent adjustment difficulties, or aggressive behaviour and attention difficulties.

The mother’s interpretation of crying behaviour may be affected by maternal depression. When they occur together, maternal depression and colic or excessive crying may affect parent-infant interactions, relationships and even child outcomes. Maternal depression adversely influences some aspects of infant development and behaviour. This applies particularly to difficulties with soothing, irritability and crying behaviour.

High-pitched or hyperphonated crying may be due to a wide range of neurobehavioral insults, including brain damage, malnutrition, asphyxia, prenatal maternal drug use, prematurity and low birth weight. High-pitched crying in infants who have prenatal risk factors may elicit caregiver responses that either improve or worsen the infant’s risk condition. In homes with less responsive parents, infants may show lower IQ scores, more withdrawn temperaments and poorer quality interactions with their mothers.

The most extreme consequences for an inconsolably crying infant are neglect and outright abuse, especially Shaken Baby Syndrome, which sometimes results in brain damage or even death.

What can be done?

The meaning of early increased, excessive or colic crying in infancy has evolved from a belief that it is abnormal or indicative of disease/dysfunction to the realization that this increased crying is a normal part of human infant development. Clinicians should be aware of the importance of crying to parents, how frustrating it can be and how it may be affecting their relationship with their infants.

When helping parents with infants who cry excessively, we should assure them that most infants who cry a great deal are healthy, and that the unpredictable, inconsolable crying usually stops spontaneously after the first few weeks. Interventions that are aimed at consoling crying infants are only partially successful, and do not reduce the inconsolable crying bouts. It is also important to recognize that variations in the sound of the cry itself may affect the reaction of the caregiver. We should be especially sensitive to caregivers experiencing depression or other condition(s) that can alter their perceptual set.

Public health information and interventions should be rigorously evaluated before being recommended as techniques for managing infant crying. Attempts should be made to create cost-effective and efficient services to meet the needs of families with young infants.

Reduction of Shaken Baby Syndrome:

Shaken Baby Syndrome is an extreme response to infant crying. Reduction in the incidence of this syndrome may be attained by public health education programs delivered early, perhaps even before the infant is born, in an effort to increase parents’ understanding of normal crying, its patterns in infancy, and how the frustration that is experienced can lead to inappropriate shaking or abuse.