Effect of prolonged uterine blood flow reduction on fetal growth in sheep. Boyle, David W., Sara Lecklitner, and Edward A. Liechty. Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana 46202-5210
APStracts 2:0220R, 1995.
The purpose of the present investigation was to study the effect of seven days of uterine blood flow reduction on fetal growth. Reduction in uterine blood flow was accomplished by external occlusion of the terminal aorta in 20 pregnant sheep. Linear growth was monitored daily by means of a crown-rump length measuring device. The deliveries of oxygen, glucose, and lactate to the fetus, as well as their uptakes by the fetus, were determined before and after seven days of uterine blood flow reduction and correlated with rates of fetal growth. Identical studies were conducted in 9 control animals. Uterine blood flow reduction resulted in a significant decrease in fetal oxygen delivery and fetal arterial oxygen content. Linear growth rate decreased by 38% in the occluded animals during hypoxemia. In addition, there was a 20% reduction in daily weight gain in occluded animals compared with controls. There were no differences in the uptakes of oxygen, glucose, and lactate by the fetus. Positive correlations were found between linear growth rate and fetal arterial oxygen content (r2 = 0.25, p = 0.0001) and between linear growth rate and fetal oxygen delivery (r2 = 0.21, p = 0.0006). The correlations between linear growth rate and fetal oxygenation provide strong evidence of the central role of oxygen in the regulation of fetal growth.

Received 8 March 1995; accepted in final form 27 July 1995.
APS Manuscript Number R153-3.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 14 August 1995.