Maternal Heart Rate Tracings in Labor as A Reflection of Personality Traits

Abstract

Personality traits are thought to be 50% heritable from pleotropic genes. Most frequently studied genes for personality traits are those of neurotransmitters. Since neurotransmitters control the autonomic nervous system, genes for neurotransmitters are candidate genes for personality traits. Heart rate and heart rate variability in response to various stimuli are thought to be an expression primarily of the autonomic nervous system and the metabolic rate. Studying heart rate and variability could reveal both autonomic nervous system function as well as personality traits. Maternal heart tracings via finger pulse oximetry are routinely a part of labor monitoring. Although not as standardized as state of the art adult heart rate variability measures, maternal heart tracings should correlate with personality testing. All patients seen in office were logged on an Excel spread sheet as to their diagnoses and were offered as a way of understanding personality connections with illness an online personality test to test aggressiveness as a sympathetic nervous system correlate as well as parasympathetic (non-aggressiveness) nervous system correlates. The test used is NPA (Narcissism, Perfectionism, and Aggression) personality test, an online test based on genetic and physiologic roots of personality. Portions of 51 laboring patients’ heart rate tracings were correlated with their results on the NPA personality test. Results showed that maternal heart rate was higher and our variability measure was lower for those with aggressive trait. Decelerations of maternal heart rate from baseline rate were found in 6 of 30 of those without aggressive trait and in none of those with aggressive trait. Accelerations of maternal heart rate from baseline rate were found in 3 of 21 of those with aggressive trait and in none of those without aggressive trait consistent with sympathetic effects on behavioral aggression and on heart rate.