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Updated: Oct 9, 2025
Noninvasive Electrocardiography in the Perinatal Mouse
Published on: June 12, 2020
Fetal ischemia monitoring with in vivo implanted electrochemical multiparametric microsensors
Samuel Dulay1, Lourdes Rivas1, Laura Pla2
1Nanobioengineering group, Institute for Bioengineering of Catalonia (IBEC) Barcelona Institute of Science and Technology (BIST), 12 Baldiri Reixac 15-21, 08028, Barcelona, Spain.
Insights
New micro-implantable sensors offer real-time monitoring for fetal ischemia. This technology aims to improve early detection of intrauterine growth restriction (IUGR) complications, potentially reducing neonatal mortality.
Area of Science:
- Biomedical Engineering
- Fetal Medicine
- Sensor Technology
Background:
- Intrauterine growth restriction (IUGR) is a major cause of neonatal morbidity and mortality.
- Current diagnostic methods like echography and cardiotocography are often inconclusive, necessitating invasive tests.
- There is a critical need for continuous, real-time monitoring of fetal well-being.
Purpose of the Study:
- To develop and validate micro-implantable multiparametric electrochemical sensors for real-time ischemia detection in fetal tissue and vasculature.
- To assess the sensitivity and selectivity of oxygen (pO2) and pH sensors for monitoring ischemic conditions.
- To demonstrate the feasibility of this technology for early detection of fetal injury.
Main Methods:
- Development of two miniaturized electrochemical sensors for oxygen and pH detection.
- In vitro optimization of sensors for selectivity and sensitivity under controlled conditions.
- In vivo validation in a ewe fetus model, implanting sensors in muscle and iliac artery.
- Induction of ischemia by controlled umbilical cord obstruction.
Main Results:
- Sensors demonstrated significant differences in pH and pO2 readings under induced normoxia and hypoxia states.
- The developed sensors showed high sensitivity required for detecting low oxygen and pH changes in fetal tissue and vasculature.
- Successful in vivo validation in a relevant large animal model.
Conclusions:
- Micro-implantable electrochemical sensors are feasible for continuous, real-time fetal monitoring.
- This technology holds promise for early detection of ischemia and prevention of fetal injury.
- The developed sensors represent a potential advancement over current diagnostic methods for IUGR.
Abstract:
Under intrauterine growth restriction (IUGR), abnormal attainment of the nutrients and oxygen by the fetus restricts the normal evolution of the prenatal causing in many cases high morbidity being one of the top-ten causes of neonatal death. The current gold standards in hospitals to detect this relevant problem is the clinical observation by echography, cardiotocography and Doppler. These qualitative techniques are not conclusive and requires risky invasive fetal scalp blood testing and/or amniocentesis. We developed micro-implantable multiparametric electrochemical sensors for measuring ischemia in real time in fetal tissue and vascular. This implantable technology is designed to continuous monitoring for an early detection of ischemia to avoid potential fetal injury. Two miniaturized electrochemical sensors were developed based on oxygen and pH detection. The sensors were optimized in vitro under controlled concentration, to assess the selectivity and sensitivity required. The sensors were then validated in vivo in the ewe fetus model, by means of their insertion in the muscle leg and inside the iliac artery of the fetus. Ischemia was achieved by gradually obstructing the umbilical cord to regulate the amount of blood reaching the fetus. An important challenge in fetal monitoring is the detection of low levels of oxygen and pH changes under ischemic conditions, requiring high sensitivity sensors. Significant differences were observed in both; pH and pO2 sensors under changes from normoxia to hypoxia states in the fetus tissue and vascular with both sensors. Herein, we demonstrate the feasibility of the developed sensors for future fetal monitoring in medical applications.
