Prolonged and unsoothable crying bouts in infants with and without colic

The authors sought to determine which features of early distress were "excessive" and specific to the first months of life as described by diary recordings. In a short-term, longitudinal, controlled study, total daily amount, frequency, and bout duration of fussing, crying, and unsoothable crying were derived from validated diaries kept by parents of infants with and without diary-defined colic at 6 weeks and 5 months recruited from primary pediatrics practices. By definition, infants with colic demonstrated more distress at 6 weeks, but they also had a much greater reduction in distress by 5 months and more distress during the fifth month. However, bout frequencies and bout durations showed different patterns. Bout duration was longer for the colic group only at 6 weeks; the difference completely disappeared by 5 months. Bout frequency was higher for the colic group at 6 weeks and 5 months, but the reduction across ages was similar in infants with and without colic. These patterns were true for all distress modalities (fussing, crying, and unsoothable crying). Unsoothable crying was present in significant amounts only at 6 weeks but virtually disappeared by 5 months. The authors conclude that prolonged distress bouts and unsoothable crying are specific to the first few months and more common, though not unique, in infants with colic. This implies that our understanding of colic may depend more on why these infants cry longer once started than what makes infants cry. These features of parental experience may be important in preventive efforts to reduce negative impacts of early increased crying such as shaken baby syndrome.