46 Maternal nutrition and developmental programming – lessons from livestock models

Abstract Our laboratories study “problems of pregnancy,” which include infertility, poor pregnancy outcomes (often reflected by fetal growth restriction and the accompanying low birthweight), and premature birth. These problems of pregnancy underpin the high incidence of low birthweight in humans (>20 million low-birthweight infants [15 to 18% of all births] per year worldwide); they also contribute to neonatal morbidity and mortality as well as developmental programming of the surviving offspring. Similarly, among livestock in the U.S. low birth weight contributes to high rates of neonatal mortality (≈10% of all births) and developmental programming of the offspring. Although there are consequences for development of many fetal organs, this talk will focus on the placenta because of its critical role in supporting pregnancy establishment, fetal growth and development, and timing of parturition. It also will focus on livestock models, as studies using livestock (e.g., cattle, horses, pigs, and sheep) have led to an improved understanding of mechanisms contributing to poor fertility, poor fetal growth/development, and premature birth. In addition, although the talk will focus primarily on the mechanisms by which maternal nutritional stress contributes to problems of pregnancy, it also will briefly discuss other stressors including multiple fetuses, maternal age, environmental stress, breed/ethnicity, and, especially, assisted reproductive technologies. Lastly, the talk will discuss recent studies focused on strategies designed to overcome the negative consequences of maternal nutritional stress and will conclude with suggestions for future research directions.