Prenatal Adversities and Latino Children’s Autonomic Nervous System Reactivity Trajectories from 6 Months to 5 Years of Age

Abbey Alkon,Brenda Eskenazi,Kim G Harley,Linh Tran,John Neuhaus,W Thomas Boyce,Jennifer Beam Dowd

doi:10.1371/journal.pone.0086283

Abstract

The purpose of the study was to determine whether mothers’ adversities experienced during early pregnancy are associated with offspring’s autonomic nervous system (ANS) reactivity trajectories from 6 months to 5 years of age. This cohort study of primarily Latino families included maternal interviews at 13–14 weeks gestation about their experience of a range of adversities: father’s absence, general social support, poverty level, and household density. ANS measures of heart rate, respiratory sinus arrhythmia (parasympathetic nervous system) and preejection period (sympathetic nervous system) were collected during resting and challenging conditions on children at 6 months and 1, 3.5 and 5 years of age. Reactivity measures were calculated as the mean of the responses to challenging conditions minus a resting condition. Fixed effects models were conducted for the 212 children with two or more timepoints of ANS measures. Interactions between maternal prenatal adversity levels and child age at time of ANS protocol were included in the models, allowing the calculation of separate trajectories or slopes for each level of adversity. Results showed no significant relations between mothers’ prenatal socioeconomic or social support adversity and offspring’s parasympathetic nervous system trajectories, but there was a statistically significant relationship between social support adversity and offspring’s heart rate trajectories (p<.05) and a borderline significant relationship between socioeconomic adversity and offspring’s sympathetic nervous system trajectories (p = .05). Children whose mothers experienced one, not two, social support adversity had the smallest increases in heart rate reactivity compared to children whose mothers experienced no adversity. The children whose mothers experienced no social support and no socioeconomic adversity had the largest increases in heart rate and preejection period respectively from 6 months to 5 years showing the most plasticity. Mothers’ prenatal adverse experiences may program their children’s physiologic trajectory to dampen their heart rate or sympathetic responsivity to challenging conditions.

Highlights

Exposure to adverse conditions during the prenatal period can alter the neurochemistry of the fetus’ central nervous system in ways that affect emotional and cognitive regulation, motor development and stress responsiveness [1,2,3,4]
There were no significant demographic differences between the 212 children included in these analyses and the full CHAMCOS sample (n = 537)
autonomic nervous system (ANS) Trajectories by Prenatal Social Support Adversity there were no significant relations between social support adversity and respiratory sinus arrhythmia (RSA) and preejection period (PEP) reactivity trajectories, there were significant relations between mothers’ prenatal level of social support adversity and children’s heart rate (HR) reactivity trajectories (Figure 1; Table 2)

Summary

Introduction

Exposure to adverse conditions during the prenatal period can alter the neurochemistry of the fetus’ central nervous system in ways that affect emotional and cognitive regulation, motor development and stress responsiveness [1,2,3,4]. Adversity experienced during sensitive periods of fetal development can program a fetus’ neurological development and affect their life course, resulting in an increased risk of disease later in life [5]. Fetal programming has been defined as a ‘‘... Studies of ‘fetal programming’ [5,6] primarily focus on the effects of adversity on children’s cortisol, an end product of hypothalmic-pituitary-adrenal (HPA) stimulation. The stress related to overcrowding during pregnancy was associated with altered glucocorticoid functioning (i.e. increased cortisol) [9]. There are several studies of children’s cortisol responses to prenatal adversity [6,7,10,11], there are few studies of children’s autonomic nervous system (ANS) responses to examine broad neurobiologic responses to prenatal adversity [12,13]

Objectives

Methods

Results

Conclusion