Abstract
To establish physiological mechanisms for fetal growth restriction in pregnant adolescent ewes we studied uterine, fetal, and uteroplacental metabolism in ewes offered a high (n = 12) or moderate (n = 10) dietary intake. High intakes decreased placental (226 vs. 414 g, P < 0.001) and fetal weight (3,323 vs. 4,626 g, P < 0.01). Uterine blood flow was reduced absolutely (-36%) but proportional to conceptus weight; umbilical blood flow was reduced absolutely (-37%) and per fetal weight (-15%). Uterine oxygen uptake was decreased per conceptus weight (-14%); there was no change in fetal weight oxygen consumption. Uteroplacental oxygen consumption and clearance were reduced proportional to weight. Similar changes were measured for glucose fluxes and fetal glucose concentration; fetal insulin concentration was reduced. In this model of fetal growth restriction, therefore, maintenance of fetal weight-specific glucose and oxygen consumption rates are producing relative hypoglycemia and hypoxemia. This indicates that increased fetal glucose clearance and/or insulin sensitivity may be operating as compensatory mechanisms to preserve normal fetal metabolism while fetal growth is sacrificed.
Original language | English |
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Pages (from-to) | R1027-R1036 |
Number of pages | 10 |
Journal | American Journal of Physiology-Regulatory Integrative and Comparative Physiology |
Volume | 282 |
Issue number | 4 |
DOIs | |
Publication status | Published - Apr 2002 |
Keywords
- uterine blood flow
- umbilical blood flow
- placenta
- fetus
- intrauterine growth restriction
- placental growth
- fetal growth
- glucose transfer
- endocrine status
- heat-stress
- retardation
- metabolism
- ewes
- consumption