Crying in the first 12 months of life: A systematic review and meta‐analysis of cross‐country parent‐reported data and modeling of the “cry curve”

Crying is an ubiquitous communicative signal in infancy. This meta‐analysis synthesizes data on parent‐reported infant cry durations from 17 countries and 57 studies until infant age 12 months (N = 7580, 54% female from k = 44; majority White samples, where reported, k = 18), from studies before the end Sept. 2020. Most studies were conducted in the United States, the United Kingdom, and Canada (k = 32), and at the traditional cry “peak” (age 5–6 weeks), where the pooled estimate for cry and fuss duration was 126 mins (SD = 61), with high heterogeneity. Formal modeling of the meta‐analytic data suggests that the duration of crying remains substantial in the first year of life, after an initial decline.