Impact of diet reduction in obese ewes during early pregnancy on placentomal type and cotyledonary vascularity in the ewe

An ovine model of over-nutrition during pregnancy is currently in development at the Center for the Study of Fetal Programming at the University of Wyoming. In 2007, an estimated 54.5% of women of childbearing age (20-39 years) are overweight or obese. This model examines the effects of maternal obesity on the health and lifespan of the offspring. Sheep were used to examine these health risks and effects, as fetal development sheep and humans is similar. In the sheep, the nutrient transfer site of the placenta is called a placentome, with both a fetal cotyledonary (COT) and a maternal caruncular component. Obese and control fed ewes were necropsied at day 135 of gestation and placentomes collected. The COT vascular bed of Type A placentomes from each ewe was perfused with a latex medium and the resulting vascular cast examined via a 3-D Scanning Electron Microscope. This allowed us to obtain an accurate measurement of COT vascularity to estimate group differences in blood flow and therefore nutrient transfer from maternal to fetal tissues. These data will be used to understand the impacts of maternal obesity on placental vascularity which may contribute to deprecating health effects of offspring later in life.