Effects of periconceptional undernutrition and twinning on ovine pregnancy
type: CreativeWork
description: Events around conception such as maternal undernutrition and twinning may have effects on offspring physiology and disease risk in adulthood. Periconceptional undernutrition alters offspring physiology and adult pathology without affecting birth size, while twinning affects birth size and physiology but with inconsistent effects on adult pathology. We investigated the effects of these two periconceptional events and their interaction on maternal cardiovascular adaptation to pregnancy and fetal growth, physiology and endocrinology in late gestation in sheep. Pre and/or postconception undernutrition resulted in increased uterine blood flow in late gestation, but no change in maternal blood volume. Preconception undernutrition alone resulted in a relatively large placenta with a small, slow-growing fetus in late gestation. In contrast, postconception undernutrition alone resulted in a fetus with rapid late-gestation growth that was maintained through a maternal fast. Fetuses of ewes undernourished throughout both periods were similar in growth rate and size to controls. Maternal fasting also demonstrated that plasma levels of C-type natriuretic peptide are acutely and independently regulated by nutrient supply in mother and fetus. Fetuses of ewes undernourished both pre- and postconception had increased glucose disposal following a glucose challenge. Hypothalamic-pituitary-adrenal axis tests in these fetuses showed decreased pituitary adrenocorticotropin hormone response to direct stimulation but increased adrenal response to decreased cortisol negative feedback. Twin fetuses grew more slowly in late gestation than singletons. Twins also had a smaller insulin response to arginine and a greater insulin response to glucose, but periconceptional undernutrition abolished this difference. Twins had suppressed baseline hypothalamic-pituitary-adrenal axis function and decreased adrenal sensitivity compared to singletons, but increased fetal pituitary adrenocorticotropin hormo…
abstract: Events around conception such as maternal undernutrition and twinning may have effects on offspring physiology and disease risk in adulthood. Periconceptional undernutrition alters offspring physiology and adult pathology without affecting birth size, while twinning affects birth size and physiology but with inconsistent effects on adult pathology. We investigated the effects of these two periconceptional events and their interaction on maternal cardiovascular adaptation to pregnancy and fetal growth, physiology and endocrinology in late gestation in sheep. Pre and/or postconception undernutrition resulted in increased uterine blood flow in late gestation, but no change in maternal blood volume. Preconception undernutrition alone resulted in a relatively large placenta with a small, slow-growing fetus in late gestation. In contrast, postconception undernutrition alone resulted in a fetus with rapid late-gestation growth that was maintained through a maternal fast. Fetuses of ewes undernourished throughout both periods were similar in growth rate and size to controls. Maternal fasting also demonstrated that plasma levels of C-type natriuretic peptide are acutely and independently regulated by nutrient supply in mother and fetus. Fetuses of ewes undernourished both pre- and postconception had increased glucose disposal following a glucose challenge. Hypothalamic-pituitary-adrenal axis tests in these fetuses showed decreased pituitary adrenocorticotropin hormone response to direct stimulation but increased adrenal response to decreased cortisol negative feedback. Twin fetuses grew more slowly in late gestation than singletons. Twins also had a smaller insulin response to arginine and a greater insulin response to glucose, but periconceptional undernutrition abolished this difference. Twins had suppressed baseline hypothalamic-pituitary-adrenal axis function and decreased adrenal sensitivity compared to singletons, but increased fetal pituitary adrenocorticotropin hormo…
author: Rumball, Christopher William Henry
language: en
keywords: developmental origins of health and disease, sheep, pregnancy, fetal programming, nutrition, twins, hypothalamic-pituitary-adrenal axis, glucose-insulin axis, fetal growth
license: https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm
date published: 2008
date modified: 2026-07-24T01:05:11Z
provider: University of Auckland
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: ResearchSpace@Auckland

PropertyValue
property ID: Handle
value: https://hdl.handle.net/2292/3290