Related Experiment Video
Updated: Aug 29, 2025
Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction
Published on: June 29, 2013
Fetal growth restriction and stillbirth: Biomarkers for identifying at risk fetuses
Victoria J King1, Laura Bennet1, Peter R Stone2
1Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand.
Insights
Fetal growth restriction (FGR) impairs fetal development and increases stillbirth risk due to placental issues. Current monitoring methods are insufficient, highlighting the need for better detection of FGR progression to prevent adverse outcomes.
Area of Science:
- Perinatal medicine
- Fetal physiology
- Obstetrics
Background:
- Fetal growth restriction (FGR) is a significant contributor to stillbirth, prematurity, and neurodevelopmental deficits.
- Many FGR cases stem from placental dysfunction, leading to reduced nutrient and oxygen supply to the fetus.
- The fetus exhibits adaptive responses to hypoxia, but progressive placental dysfunction can overwhelm these mechanisms.
Purpose of the Study:
- To review the diagnostic challenges and limitations of current screening and monitoring practices for FGR.
- To explore methods for improved FGR identification and the critical "tipping point" of fetal adaptation.
- To enhance the management of pregnancies complicated by FGR to mitigate risks of fetal hypoxia and preterm birth.
Main Methods:
- Review of current literature on FGR etiology, pathophysiology, and surveillance.
- Analysis of diagnostic limitations in fetal Doppler ultrasound and heart rate monitoring.
- Discussion of potential advancements in identifying FGR and predicting fetal compromise.
Main Results:
- Current surveillance methods for FGR have significant limitations, with nearly half of cases undetected prenatally.
- Conventional monitoring fails to prevent a substantial proportion of FGR-related stillbirths.
- Identifying the critical threshold of fetal hypoxia and acidosis remains a major challenge.
Conclusions:
- Improved detection and monitoring of FGR progression are crucial for managing complicated pregnancies.
- There is a critical need for enhanced methods to identify fetuses at risk of acidosis and stillbirth.
- Balancing the risks of in utero hypoxia against iatrogenic preterm birth requires better diagnostic tools.
Abstract:
Fetal growth restriction (FGR) is a major cause of stillbirth, prematurity and impaired neurodevelopment. Its etiology is multifactorial, but many cases are related to impaired placental development and dysfunction, with reduced nutrient and oxygen supply. The fetus has a remarkable ability to respond to hypoxic challenges and mounts protective adaptations to match growth to reduced nutrient availability. However, with progressive placental dysfunction, chronic hypoxia may progress to a level where fetus can no longer adapt, or there may be superimposed acute hypoxic events. Improving detection and effective monitoring of progression is critical for the management of complicated pregnancies to balance the risk of worsening fetal oxygen deprivation in utero, against the consequences of iatrogenic preterm birth. Current surveillance modalities include frequent fetal Doppler ultrasound, and fetal heart rate monitoring. However, nearly half of FGR cases are not detected in utero, and conventional surveillance does not prevent a high proportion of stillbirths. We review diagnostic challenges and limitations in current screening and monitoring practices and discuss potential ways to better identify FGR, and, critically, to identify the "tipping point" when a chronically hypoxic fetus is at risk of progressive acidosis and stillbirth.
