Duration and pattern of crying in the first year of life.

In a prospective study of fetal and postnatal growth and development in a group of babies whose mothers were residents of an inner-city health district in the north of England, the total amount of crying of 157 infants was recorded at four periods during the first year of life by means of a 24-hour log. The mean number of crying episodes reduced from 4.4 at six weeks to 1.5 at one year. Early crying predicted later crying. It was not possible to predict which babies would cry a lot except that breast-fed infants tended to cry less. Mothers' perceptions of whether their babies cried a lot correlated with their perception of sleep difficulties. Rapid response to crying was associated with significantly less crying overall.