Fetal Metabolic Response to Maternal Starvation

Abstract

Extract: In the pregnant ewe in the fed state, higher maternal protein intake does not lead to increased protein catabolism by the fetus. Total maternal starvation results in a prompt fall in fetal glucose concentrations (by 35%) to a stable plateau by 48 hr of starvation. Transplacental glucose uptakes during prolonged starvation are less than 40% of normal fed state values. Fetal urea production rates (a reflection of amino acid catabolism) increase to a level twice the fed state values by the 4th day of starvation and then return to base-line values by the 7th day of starvation. Fetal glucose concentrations remain stable throughout prolonged starvation, even after urea production rates have returned to base-line values.

Speculation: At the peak of urea production, amino acid catabolism by the fetus can account for at least 80% of fetal oxygen consumption. However, the mechanisms and substrates available for homeostasis during the first 2 days (and after the 7th day of starvation) are unknown and, in the face of depressed transplacental glucose uptakes, may put the fetus at significant risk.

Log in or create a free account to read this content

Gain free access to this article, as well as selected content from this journal and more on nature.com

Access through your institution

or

Sign in or create an account

Continue with Google

Continue with ORCiD