Intrauterine blood flow and postnatal development.

Fetal experience forms the basis for postnatal life. This relationship may be obvious in the newborn infant, although it is sometimes not apparent until later in development. One fetal condition with known implications for later life is intrauterine growth restriction (IUGR), which ranges from being an important factor in perinatal mortality to affecting morbidity in adulthood.
The process of growth, usually measurable as change in anatomical size, is intimately related to that of development, the latter referring to a gradual acquisition of physiological function. Dobbing defined the brain growth spurt as that transient period of growth when the brain is growing most rapidly and the period of time when the brain is most susceptible to adverse influence [1]. Fetal malnutrition during the brain growth spurt may reduce the number of synapses per neuron by 40% [2]. Other authors have demonstrated a lower myelin lipid content in the brain of a small-for-gestational age (SGA) newborn as compared with that of an appropriate-for-gestational age (AGA) newborn [3, 4]. In the human, a large part of the brain growth spurt takes place in the years after birth; therefore, the nutritional as well as the psychosocial environment during the first postnatal years may add to, but equally compensate for, previous adverse influence during fetal development.