Gluckman P D, Hanson M A
Liggins Institute and National Research Centre for Growth and Development, University of Auckland, New Zealand.
Horm Res. 2006;65 Suppl 3:5-14. doi: 10.1159/000091500. Epub 2006 Apr 10.
Absolute definitions of fetal growth are being replaced by definitions that focus on an optimal life-course trajectory. The fetus makes responses to its environment that are determined by the maternal macro-environment, health and physiology. The processes of maternal constraint create significant variations within the normal range of maternal environments and function, and in the fetal environment, which are reflected in different patterns of growth. Deficient nutrient provision may induce immediate adaptation in the form of fetal growth impairment, but will also induce adaptive responses that have evolved for predictive advantage; that is, for a later phase of the life cycle. This latter class of response, probably mediated by epigenetic processes, explains many outcomes of a less-than-optimal pregnancy, including impaired growth, increased visceral obesity, impaired cognitive development, advanced maturation and a greater risk of metabolic and related disease in later life. While these adaptive processes evolved and were appropriate in the environments of prehistory, they are increasingly mismatched with modern environments. Such considerations suggest different approaches to intervention and prevention in population-specific contexts.
胎儿生长的绝对定义正被关注最佳生命历程轨迹的定义所取代。胎儿会对其所处环境做出反应，而这种反应由母亲的宏观环境、健康状况和生理机能所决定。母亲的限制因素会在母亲环境和功能的正常范围内以及胎儿环境中产生显著差异，这些差异反映在不同的生长模式中。营养供应不足可能会立即导致胎儿生长受损，从而引发适应性反应，但也会引发为了预测优势而进化出的适应性反应；也就是说，为了生命周期的后期阶段。后一类反应可能由表观遗传过程介导，它解释了许多不太理想的孕期所产生的后果，包括生长发育受损、内脏肥胖增加、认知发育受损、早熟以及晚年患代谢及相关疾病的风险增加。虽然这些适应性过程是在史前环境中进化而来且适应当时环境，但它们与现代环境越来越不匹配。这些考虑因素表明，在针对特定人群的情况下，干预和预防的方法会有所不同。
