OBJECTIVE: To study how the early crying behavior of preterm infants at term, 6 weeks, and 5 months of corrected age is related to later behavioral problems at age 3 and 4 years and parenting stress at 2 and 4 years.

METHODS: The study group included 202 live-born, low birth weight infants (birth weight ≤1500 g) born from January 2001 through December 2006 at the Turku University Hospital, Finland. A Baby Day Diary was used to assess the preterm infants’ crying behavior at term, 6 weeks, and 5 months of corrected age. The children’s behavior was assessed using the Child Behavior Check List at 3 and 4 years old, and parenting stress was assessed by using the Parenting Stress Index when the child was 2 and 4 years old.

RESULTS: The duration and frequency of crying bouts in infancy was associated with Child Behavior Check List scores at 4 years old and to both mothers’ and fathers’ stress when the child was 2 and 4 years old.

CONCLUSIONS: Early excessive crying, especially if lasting up to 5 months of corrected age, is a clinically relevant signal in preterm infants because it may reflect infants’ regulatory problems and/or parenting stress. The crying behavior of preterm infants should be systematically inquired about at well-baby clinics.