[Fetal weight at weight as predisposing risk factor for type 2 diabetes in adulthood]

When the fetus growth in an unfavorable intrauterine environment, this process has implications in the adult life, that predisposes to suffer metabolic abnormalities as obesity, hypertension and non-insulin dependent diabetes mellitus. The unfavorable intrauterine environment includes the pregnancy with diabetes mellitus, pregnancy with gestational diabetes, and pregnancy with maternal undernutrition. Multiple epidemiological studies developed in North America and Europe appear to broadly confirm the association of the low birth weight in babies borne at term, with the glucose metabolism impairments in the adult life. An implication of metabolic impairments on high birth weight for the gestational age has been founded. This alteration could start when there are changes in nutritional habits in migrate populations, having number and function of the pancreatic islets altered, maybe because during fetal life they were faced to blood fluid decreased, and nutrients also decrease as well as the differentiation of cells was modified, as an important intent for fetal survival. The prevalence of type 2 diabetes has been reported in 13 to 25% for low birth weight. On the other hand, maternal hyperglycemia leads to beta-cell hyperplasia in the fetus, by a constant stimulus over the insulin production which stimulates the use of glucose as nutrients, leading to the increase in fetal weight and determining genetic changes. In overnutrition conditions, the prevalence of type 2 diabetes has been reported of 8 to 18%. Growth of tissues has critical periods at different times and intrauterine environment can be one mechanism for may permanently changes in pancreas structure and hormonal secretion patterns. Thus, the hypothesis that autoprotective fetal changes during the intrauterine life occur, took place, specially during the critical period of development, leaves to permanent changes called "programmed changes", including an endocrine disturbance of pancreatic functions, appearing in adult life. Further molecular studies of pancreatic islets are necessary in order to determine the mechanisms for lifelong changes and insulin metabolism due to intrauterine growth.