Biological mechanisms for nutritional regulation of maternal health and fetal development.

This review paper highlights mechanisms for nutritional regulation of maternal health and fetal development. Malnutrition (nutrient deficiencies or obesity) in pregnant women adversely affects their health by causing or exacerbating a plethora of problems, such as anaemia, maternal haemorrhage, insulin resistance, and hypertensive disorders (e.g. pre-eclampsia/eclampsia). Maternal malnutrition during gestation also impairs embryonic and fetal growth and development, resulting in deleterious outcomes, including intrauterine growth restriction (IUGR), low birthweight, preterm birth, and birth defects (e.g. neural tube defects and iodine deficiency disorders). IUGR and preterm birth contribute to high rates of neonatal morbidity and mortality. Major common mechanisms responsible for malnutrition-induced IUGR and preterm birth include: (i) abnormal growth and development of the placenta; (ii) impaired placental transfer of nutrients from mother to fetus; (iii) endocrine disorders; and (iv) disturbances in normal metabolic processes. Activation of a series of physiological responses leading to premature and sustained contraction of the uterine myometrium also results in preterm birth. Recent epidemiologic studies have suggested a link between IUGR and chronic metabolic disease in children and adults, and the effects of IUGR may be carried forward to subsequent generations through epigenetics. While advanced medical therapies, which are generally unavailable in low-income countries, are required to support preterm and IUGR infants, optimal nutrition during pregnancy may help ameliorate many of these problems. Future studies are necessary to develop effective nutritional interventions to enhance fetal growth and development and alleviate the burden of maternal morbidity and mortality in low- and middle-income countries.