Early life stress has been shown to influence the developing autonomic nervous system.
Stressors in infancy may program the autonomic nervous system resting state set point,
affecting cardiovascular function in later life. Excessive crying may be an indicator of
increased stress arousal in infancy. We hypothesized that excessive infant crying is related
to altered cardiac autonomic nervous system activity and increased blood pressure at age
In the Amsterdam Born Children and their Development study, excessive crying, maternal
burden of infant care and maternal aggressive behavior in the 13th week after birth (range
11±16 weeks) were reported using questionnaires. Blood pressure, heart rate, heart rate
variability and indicators of cardiac autonomic nervous system activity (sympathetic drive by
pre-ejection period, parasympathetic drive by respiratory sinus arrhythmia) were measured
at age 5±6 years during rest. Inclusion criteria were singleton birth, term-born, and no
reported congenital or cardiovascular problems (N = 2153 included).
Results: Excessive crying (2.8%) was not associated with resting heart rate, heart rate variability,
pre-ejection period, respiratory sinus arrhythmia nor with blood pressure at age 5±6 years.
Excessive infant crying as an indicator of increased stress arousal does not seem to be
related to resting activity of the autonomic nervous system or blood pressure at age 5±6.
Potential associations may become visible under stressed conditions.