Maternal Stress and Fetal/Infant Development

最近的证据表明，人类胎儿暴露在对健康具有永久性影响的深刻影响中。母体压力会引发一系列事件，改变人类胎儿的正常发育过程。暴露在高压力信号下的人类胎儿在宫内学习受到损害，早产和低出生体重的风险增加了三倍。此外，多达一半的早产儿或小儿生有运动、感觉或认知障碍。这项为期五年的建议的主要目的是确定产前母亲应激和母亲神经内分泌反应对胎儿行为的影响，并评估200名妇女(一半是盎格鲁人，一半是西班牙人)胎儿行为和婴儿发育之间的关系。具体目标是：(A)确定影响胎儿行为的主要压力因素；(B)婴儿发育。怀孕期间将对压力进行五次测量(访谈和问卷调查)。胎儿的行为和发育将通过传统的胎儿生长测量和胎儿行为状态、运动(休息和挑战)、反应性和胎心率(FHR)习惯化的测量来量化。将使用贝利发育量表、神经运动状态检查以及基础和昼夜节律测量下丘脑-垂体-肾上腺(HPA)活动来评估婴儿的行为：(C)确定母亲应激相关(HPA)轴活动和失调对胎儿和婴儿行为以及婴儿HPA活动的影响。由于母体应激改变了胎鼠大脑中的多肽受体和脑多肽水平，而且它影响了人类的胎儿行为和出生结果，因此将从每次探视时获取的血液中检测母体多肽水平。母体应激肽对婴儿行为和HPA活性的影响将在6周、6个月、12个月和24个月时确定。(D)描述胎儿行为与婴儿结局之间的关系。胎儿中枢神经系统活动(习惯化)的灵敏测量将与静止和挑战后胎儿行为的当代测量相结合，以描述胎儿的成熟。这些措施将被输入预测婴儿神经运动发育的模型中。该项目旨在通过检查应激的时间和持续时间，通过调查与产前应激有关的生物机制，特别是HPA和胎盘轴，以及通过对婴儿产前应激的发育后果进行纵向研究，来确定对胎儿有害的母亲应激状况。

Recent evidence indicates that the human fetus is exposed to profound influences that have permanent implications for health. Maternal stress initiates a cascade of events that alter normal developmental processes in the human fetus. Human fetuses exposed to elevated stress signals have impaired learning in utero and are at three-fold increased risk for preterm birth and low birth weight. Moreover, as many as one-half of the infants born early or small, have motor, sensory or cognitive handicaps. The primary aim of this five-year proposal is to determine the influence of prenatal maternal stress and maternal neuroendocrine responses on fetal behavior and to assess the relationship between fetal behavior and infant development in a sample of 200 women (one-half Anglo, one-half Hispanic). The specific aims are to: (a) Identify the primary stress factors that influence fetal behavior and (b) infant development. Stress will be measured (interviews and questionnaires) five times during pregnancy. Fetal behavior and development will be quantified by conventional measures of fetal growth and by measures of fetal behavioral state, movement (at rest and challenge), reactivity and habituation of fetal heart rate (FHR). Infant behavior will be assessed with the Bayley scales of Development, the Neuromotor Status Examination and by basal and circadian measures of hypothalamic-pituitary-adrenal (HPA) activity: (c) Determine the influence of maternal stress-related (HPA) axis activity and disregulation on fetal and infant behavior and infant HPA activity. Because maternal stress alters peptide receptors and brain peptide levels in the fetal rat brain and because it influences human fetal behavior and birth outcomes, maternal peptide levels will be assayed from blood obtained at each visit. The influence of maternal stress peptides on infant behavior and HPA activity will be determined at six weeks, six, twelve and twenty-four months. (d) Describe the relationship between fetal behavior and infant outcome. A sensitive measure of fetal CNS activity (habituation) will be integrated with contemporary measures of fetal behavior at rest and after challenge, to describe fetal maturation. These measures will be entered into models to predict infant neuromotor development. This project is designed to identify maternal stressful conditions that are harmful to the fetus by examination of the timing and duration of stress, by investigation of biological mechanisms related to prenatal stress, specifically the HPA and placental axis and by longitudinal studies of developmental consequences of prenatal stress in the infant.