Blood flows and nutrient uptakes in growth-restricted  pregnancies induced by overnourishing adolescent sheep

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.

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Fetal Growth Restriction Is Associated With Prioritization of Umbilical Blood Flow to the Left Hepatic Lobe at the Expense of the Right Lobe

Pediatric Research ◽

10.1203/pdr.0b013e3181a29077 ◽

2009 ◽

Vol 66 (1) ◽

pp. 113-117 ◽

Cited By ~ 26

Author(s):

Jörg Kessler ◽

Svein Rasmussen ◽

Keith Godfrey ◽

Mark Hanson ◽

Torvid Kiserud

Keyword(s):

Blood Flow ◽

Fetal Growth ◽

Fetal Growth Restriction ◽

Growth Restriction ◽

Left Hepatic Lobe ◽

Hepatic Lobe ◽

Umbilical Blood ◽

Right Lobe ◽

Umbilical Blood Flow ◽

The Right

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DIAGNOSIS AND MANAGEMENT OF SELECTIVE FETAL GROWTH RESTRICTION IN MONOCHORIONIC TWINS

Fetal and Maternal Medicine Review ◽

10.1017/s0965539509990106 ◽

2009 ◽

Vol 20 (4) ◽

pp. 269-281 ◽

Cited By ~ 1

Author(s):

EDUARD GRATACÓS ◽

ELISENDA EIXARCH ◽

FATIMA CRISPI

Keyword(s):

Fetal Growth ◽

Common Sense ◽

Fetal Growth Restriction ◽

Growth Restriction ◽

Fetal Weight ◽

Abdominal Circumference ◽

Monochorionic Twins ◽

Normal Ranges ◽

Estimated Fetal Weight ◽

Simple Definition

Selective fetal growth restriction (sFGR) has been reported to occur in about 10–15% of monochorionic (MC) twins. The diagnosis of sFGR has been based on variable criteria including estimated fetal weight (EFW), abdominal circumference and/or the degree of fetal weight discordance. Recent studies tend to use a simple definition which includes the presence of an EFW less than the 10th percentile in the smaller twin. Some would argue that the intertwin fetal weight discordance should be included in the definition. Indeed this factor plays a major role in the complications presented by these cases. While the majority of cases with one fetus below the 10th percentile usually will also present with a large intertwin EFW discordance, the contrary is not always true. Thus, it is possible to find MC twins with remarkable intertwin EFW discordance but the EFW of both fetuses are still within normal ranges. Although it appears to be common sense that a large intertwin discrepancy might represent a higher risk for some of the complications described later in this review, there is no consistent evidence to support this notion. Therefore, due to its simplicity, a definition based on an EFW below 10th percentile in one twin is probably the most useful for clinical and research purposes.

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Enhanced Nitrite-Mediated Relaxation of Placental Blood Vessels Exposed to Hypoxia Is Preserved in Pregnancies Complicated by Fetal Growth Restriction

International Journal of Molecular Sciences ◽

10.3390/ijms22094500 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4500

Author(s):

Teresa Tropea ◽

Carina Nihlen ◽

Eddie Weitzberg ◽

Jon O. Lundberg ◽

Mark Wareing ◽

...

Keyword(s):

Blood Flow ◽

Blood Vessels ◽

Fetal Growth ◽

Fetal Growth Restriction ◽

Plasma Concentrations ◽

Growth Restriction ◽

Alternative Source ◽

Fetal Plasma ◽

Placental Blood ◽

Nitrate And Nitrite

Nitric oxide (NO) is essential in the control of fetoplacental vascular tone, maintaining a high flow−low resistance circulation that favors oxygen and nutrient delivery to the fetus. Reduced fetoplacental blood flow is associated with pregnancy complications and is one of the major causes of fetal growth restriction (FGR). The reduction of dietary nitrate to nitrite and subsequently NO may provide an alternative source of NO in vivo. We have previously shown that nitrite induces vasorelaxation in placental blood vessels from normal pregnancies, and that this effect is enhanced under conditions of hypoxia. Herein, we aimed to determine whether nitrite could also act as a vasodilator in FGR. Using wire myography, vasorelaxant effects of nitrite were assessed on pre-constricted chorionic plate arteries (CPAs) and veins (CPVs) from normal and FGR pregnancies under normoxic and hypoxic conditions. Responses to the NO donor, sodium nitroprusside (SNP), were assessed in parallel. Nitrate and nitrite concentrations were measured in fetal plasma. Hypoxia significantly enhanced vasorelaxation to nitrite in FGR CPAs (p < 0.001), and in both normal (p < 0.001) and FGR (p < 0.01) CPVs. Vasorelaxation to SNP was also potentiated by hypoxia in both normal (p < 0.0001) and FGR (p < 0.01) CPVs. However, compared to vessels from normal pregnancies, CPVs from FGR pregnancies showed significantly lower reactivity to SNP (p < 0.01). Fetal plasma concentrations of nitrate and nitrite were not different between normal and FGR pregnancies. Together, these data show that nitrite-mediated vasorelaxation is preserved in FGR, suggesting that interventions targeting this pathway have the potential to improve fetoplacental blood flow in FGR pregnancies.

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Aspirin pre-treatment modulates ozone-induced fetal growth restriction and alterations in uterine blood flow in rats

Reproductive Toxicology ◽

10.1016/j.reprotox.2018.12.002 ◽

2019 ◽

Vol 83 ◽

pp. 63-72 ◽

Cited By ~ 3

Author(s):

Colette N. Miller ◽

Urmila P. Kodavanti ◽

Erica J. Stewart ◽

Mette Schaldweiler ◽

Judy H. Richards ◽

...

Keyword(s):

Blood Flow ◽

Fetal Growth ◽

Fetal Growth Restriction ◽

Growth Restriction ◽

Uterine Blood Flow ◽

Pre Treatment

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EARLY MARKERS OF DIAGNOSIS FETAL GROWTH RESTRICTION SYNDROME

Reproductive Medicine ◽

10.37800/rm2020-1-23(2) ◽

2020 ◽

pp. 48-51

Author(s):

G.A. Ikhtiyarova ◽

M.J. Aslonova ◽

N.K. Dustova

Keyword(s):

Blood Flow ◽

Fetal Growth ◽

Fetal Growth Restriction ◽

Growth Restriction ◽

Second Trimester ◽

Early Markers ◽

Uteroplacental Blood Flow ◽

Placental Blood ◽

Placental Blood Flow ◽

Large Vessels

The article presents the effectiveness of Dopplerometry for assessing blood flow in large vessels, including the umbilical, uterine artery and middle cerebral artery, 90 women were examined in the second trimester, and 45 women showed signs of placental insufficiency, such as fetal growth restriction syndrome at 28-34 weeks. The results of the study showed that 23 (51.1%) women had signs of subcompensated insufficiency of uteroplacental blood flow, and 11 (24.4%) women showed signs of fetal-placental blood flow. The study of the uteroplacental-fetal blood flow allows early detection of early signs of impairment in the fetoplacental system and its timely correction.

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Description of a method for inducing fetal growth restriction in the spiny mouse

Journal of Developmental Origins of Health and Disease ◽

10.1017/s2040174417000393 ◽

2017 ◽

Vol 8 (5) ◽

pp. 550-555 ◽

Cited By ~ 2

Author(s):

H. Dickinson ◽

S. Ellery ◽

M. Davies-Tuck ◽

M. Tolcos ◽

I. Nitsos ◽

...

Keyword(s):

Blood Flow ◽

Fetal Growth ◽

Gestational Age ◽

Fetal Growth Restriction ◽

Fetal Loss ◽

Small Animal ◽

Major Complication ◽

Growth Restriction ◽

Spiny Mouse ◽

Uterine Blood Flow

Intrauterine or fetal growth restriction (IUGR) is a major complication of pregnancy and leads to significant perinatal morbidities and mortality. Typically, induction of IUGR in animals involves the complete occlusion or ablation of vessels to the uterus or placenta, acutely impairing blood flow and fetal growth, usually with high fetal loss. We aimed to produce a model of reduced fetal growth in the spiny mouse with minimal fetal loss. At 27 days gestational age (term is 38–39 days), a piece of silastic tubing was placed around the left uterine artery to prevent the further increase of uterine blood flow with advancing gestation to induce IUGR (occluded). Controls were generated from sham surgeries without placement of the tubing. Dams were humanely euthanized at 37 days gestational age and all fetuses and placentas were weighed and collected. Of the 17 dams that underwent surgery, 15 carried their pregnancies to 37 days gestational age and 95% of fetuses survived to this time. The difference in fetal body weight between occluded and control was ~21% for fetuses in the left uterus side: there were no differences for fetuses in the right uterus side. Offspring from the occluded group had significantly lower brain, liver, lung, kidney and carcass weights compared with shams. Preventing the gestation-related increase of uterine blood flow induced significant growth restriction in the fetal spiny mouse, with minimal fetal loss. This technique could be readily adapted for other small animal.

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