Fetal Heart Rate Monitoring Research Articles

Fetal-hope study: Home monitoring of fetal heart rate in SSA + pregnant women: Rationale and design

IntroductionWorldwide, approximately 0.5–1 % of women of childbearing age are positive for anti-Ro/SSA antibodies and anti-La/SSB. The presence of these antibodies may be responsible for the appearance of Neonatal Lupus. The pathogenesis of this disease is probably mediated by the binding of these antibodies to fetal myocardiocytes. The typical manifestation is atrioventricular block (AVB), which in most cases is complete (CHB). AVB commonly develops between 16 and 26 weeks of gestation and is cause of severe heart failure. CHB appears to be irreversible, but anecdotal reports suggest that treatment of second-degree AVB can restore sinus rhythm. ObjectiveThe aim of the study is to evaluate the reliability of home monitoraing of fetal heart rate by the use of a hand-held device, extablishing the incidence of fetal AVB in pregnant women positive for anti-Ro/SSA autoantibodies and to evaluate whether early treatment can influence the course of the disease. MethodsAnti-Ro/SAA positive pregnant women are currently recruited from 11 Italian centers in a prospective observational study. Patients are instructed to use a portable doppler between 16 and 34 weeks of gestation and to monitor the fetal heart rate (FHR) every 8 h. In case of FHR anomalies patients will contact the reference center which will guarantee an echocardiogram within 8 h and in case of anomalies, adequate treatment. All patients will undergo check-ups at 20, 26 and 32 weeks of gestation, with the collection of information on the course of the maternal disease, on the use of drugs and on instrumental monitoring progress.After birth, data will be collected on the outcome of pregnancy and the methods of delivery. Newborns will also be evaluated for the possible appearance of clinical signs of Neonatal Lupus. ResultsFetal-Hope is actually enrolling Patients from involved Centers. ConclusionsFetal-Hope is the first European study assessing the reliability of home monitoring of fetal heart rate using a handheld device, determining the incidence of fetal atrioventricular block (AVB) in pregnant women positive for anti-Ro/SSA autoantibodies and assessing whether early intervention can alter the disease’s progression.

Intrapartum Cardiotocography With Simultaneous Maternal Heart Rate Registration Improves Neonatal Outcome

(Abstracted from Am J Obstet Gynecol 2024;230:379.e1–379.e12) Cardiotocography (CTG) is the most common fetal surveillance method during delivery, involving simultaneous monitoring of uterine activity and fetal heart rate (FHR). Newer CTG monitors also track maternal heart rate (MHR), to prevent artifacts from disturbing FHR detection.

The Subtle Signs Of Neonatal Grave’s Disease- ACase Report And Review

A newborn male is born via caesarean section at 37 weeks of gestation to a 25-year-old primigravida mother. Mother was a known case of Grave’s disease (TSH receptor antibody positive) on Carbimazole with gestational diabetes mellitus on Insulin, her antenatal course was otherwise uneventful, with normal fetal heart rate monitoring and appropriate fetal growth. She was admitted with complaints of pain abdomen and decreased fetal movement. She was planned for emergency section and a live, healthy male baby was born with a birth weight of 2.962 kg, appropriate for gestation age with APGAR 8/9. Postnatal examination was negative for congenital anomalies and no systemic involvement was noticed. The baby was discharged on close follow-up. On day 7th of life, the baby was re-admitted for phototherapy. In this admission, the baby was noticed to have a resting tachycardia heart rate of 170-180/min, no murmur or abnormal heart sound was noticed on examination. The baby had no significant weight loss or history of feeding difficulties. In consideration of maternal grave disease, a further workup for the baby was planned, which revealed a Cord TSH (0.007microIU/ml) range (2.30-13.20) and free T4 1.52 ng/dl (Range 1.10-2.00). Further, the workup revealed TSH receptor antibody positive 23.76 IU/L range (less than 1.22), free T4 7.77 ng/dl (1.120-2.00), TSH less than 0.005 microIU/ml. However, As per the paediatric Endocrinologist's opinion, the baby was started on propranolol and propylthiouracil. The resting tachycardia resolved upon starting the drug. On subsequent follow-up, the baby had an improving thyroid profile

Spontaneous Umbilical Cord Vascular Rupture during Labor: A Retrospective Analysis of 12 Cases.

Umbilical cord vascular rupture is a rare and severe condition that can occur during labor, leading to adverse outcomes for the fetus before as well as after delivery. Prompt diagnosis and intervention are crucial for improving the chances of a successful outcome. We aimed to analyze cases of umbilical cord vascular rupture during labor to provide insights into this challenging condition. This retrospective study evaluated the medical records of patients diagnosed with umbilical cord vessel rupture or umbilical cord hematoma at Fujian Maternity and Child Health Hospital from January 1, 2015, to May 31, 2023. The inclusion criteria included gestational age of ≥28 weeks, occurrence during labor, and availability of complete delivery data. Data on fetal heart rate (FHR) changes, delivery intervals, intraoperative findings, placental pathology, and neonatal outcomes were collected and analyzed. A total of 12 cases were analyzed. The incidence of umbilical cord vascular rupture during childbirth was 0.08%. The FHR patterns in umbilical cord rupture during delivery included baseline tachycardia, minimal or absent variability, variable or late deceleration, prolonged deceleration, and undetectable heart rate. The bradycardia-to-delivery interval (BDI) ranged from 6 to 26 minutes. Among the 12 neonates, 9 were discharged well, 2 were stillbirths, and there was 1 neonatal death. Hemorrhagic shock was common in live births. Our study highlights the significance of continuous FHR monitoring during labor and the urgent need for medical teams to respond quickly in cases of umbilical cord vascular rupture. Despite advancements in neonatal resuscitation techniques, managing cases with undetectable fetal heart activity remains clinically challenging, and even with immediate pregnancy termination, poor neonatal outcomes may still occur. · Umbilical cord vascular rupture during labor is a rare event.. · Its clinical management presents significant challenges.. · Advances in neonatal resuscitation have improved rescue success rates.. · In such cases, hemorrhagic shock is common in live births..

Emerging Paradigms in Fetal Heart Rate Monitoring: Evaluating the Efficacy and Application of Innovative Textile-Based Wearables.

This comprehensive review offers a thorough examination of fetal heart rate (fHR) monitoring methods, which are an essential component of prenatal care for assessing fetal health and identifying possible problems early on. It examines the clinical uses, accuracy, and limitations of both modern and traditional monitoring techniques, such as electrocardiography (ECG), ballistocardiography (BCG), phonocardiography (PCG), and cardiotocography (CTG), in a variety of obstetric scenarios. A particular focus is on the most recent developments in textile-based wearables for fHR monitoring. These innovative devices mark a substantial advancement in the field and are noteworthy for their continuous data collection capability and ergonomic design. The review delves into the obstacles that arise when incorporating these wearables into clinical practice. These challenges include problems with signal quality, user compliance, and data interpretation. Additionally, it looks at how these technologies could improve fetal health surveillance by providing expectant mothers with more individualized and non-intrusive options, which could change the prenatal monitoring landscape.

Deep learning with information fusion and model interpretation for long-term prenatal fetal heart rate data

Long-term fetal heart rate (FHR) monitoring during the antepartum period, increasingly popularized by electronic FHR monitoring, represents a growing approach in FHR monitoring. This kind of continuous monitoring, in contrast to the short-term one, collects an extended period of fetal heart data. This offers a more comprehensive understanding of fetus’s conditions. However, the interpretation of long-term antenatal fetal heart monitoring is still in its early stages, lacking corresponding clinical standards. Furthermore, the substantial amount of data generated by continuous monitoring imposes a significant burden on clinical work when analyzed manually. To address above challenges, this study develops an automatic analysis system named LARA (Long-term Antepartum Risk Analysis system) for continuous FHR monitoring, combining deep learning and information fusion methods. LARA’s core is a well-established convolutional neural network (CNN) model. It processes long-term FHR data as input and generates a Risk Distribution Map (RDM) and Risk Index (RI) as the analysis results. We evaluate LARA on inner test dataset, the performance metrics are as follows: AUC 0.872, accuracy 0.816, specificity 0.811, sensitivity 0.806, precision 0.271, and F1 score 0.415. In our study, we observe that long-term FHR monitoring data with higher RI is more likely to result in adverse outcomes (p = 0.0021). In conclusion, this study introduces LARA, the first automated analysis system for long-term FHR monitoring, initiating the further explorations into its clinical value in the future.

Case Report: Peripartum periventricular leukomalacia resulting in cerebral palsy associated with placenta previa in Japan

Intrapartum fetal heart rate monitoring abnormalities had been reported to correlate with decreased umbilical artery base excess associated with neonatal seizures. However, we present an infant born at 35 weeks of gestation diagnosed with cerebral palsy associated with periventricular leukomalacia (PVL) without fetal heart rate (FHR) monitoring abnormalities, According to the summary reports of PVL cases published on the home page of the Japan Obstetric Compensation System for Cerebral Palsy (JOCSC)), the percentage of placenta previa without FHR monitoring abnormalities in the cases of PVL was 5.7% (12/209), which seemed to be higher than the total percentage of placenta previa reported in Japan (0.3–0.5%).

Adopting artificial intelligence algorithms for remote fetal heart rate monitoring and classification using wearable fetal phonocardiography

Fetal phonocardiography (FPCG) is a non-invasive Fetal Heart Rate (FHR) monitoring technique that can detect vibrations and murmurs in heart sounds. However, acquiring fetal heart sounds from a wearable FPCG device is challenging due to noise and artefacts. This research contributes a resilient solution to overcome the conventional issues by adopting Artificial Intelligence (AI) with FPCG for automated FHR monitoring in an end-to-end manner, named (AI-FHR). Four sequential methodologies were used to ensure reliable and accurate FHR monitoring. The proposed method removes low-frequency noises and high-frequency noises by using Chebyshev II high-pass filters and Enhanced Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (ECEEMDAN) in combination with Phase Shifted Maximal Overlap Discrete Wavelet Transform (PS-MODWT) filters, respectively. The denoised signals are segmented to reduce complexity, and the segmentation is performed using multi-agent deep Q-learning (MA-DQL). The segmented signal is provided to reduce the redundancies in cardiac cycles using the Artificial Hummingbird Optimization (AHBO) algorithm. The segmented and non-redundant signals are converted into 3D spectrograms using a machine learning algorithm called variational auto-encoder-general adversarial networks (VAE-GAN). The feature extraction and classification are carried out by adopting a hybrid of the bidirectional gated recurrent unit (BiGRU) and the multi-boosted capsule network (MBCapsNet). The proposed method was implemented and simulated using MATLAB R2020a and validated by adopting effective validation metrics. The results demonstrate that the proposed method performed better than the current method with accuracy (81.34%), sensitivity (72%), F1-score (83%), Energy (0.808 J), and complexity index (13.34). Like other optimization methods, AHO needs precise parameter adjustment in order to function well. Its performance may be greatly impacted by the selection of parameters, including population size, exploration rate, and learning rate.

AI in Perinatal Medicine and Human Reproduction: Artificial IntelligenceAI in Perinatal Medicine and Human Reproduction: Is it “The End of the Beginning” or “The Beginning of the End”?

The paper explores the evolving role of Artificial Intelligence (AI) in perinatal medicine and hu-man reproduction, highlighting its potential to transform clinical practices. AI technologies are being utilized to improve diagnostic accuracy, personalize treatment, and enhance patient care, particularly in areas like perinatal ultrasound, fetal heart rate monitoring, and fetal neurology. The Kurjak Antenatal Neurodevelopmental Test (KANET) exemplifies how AI can aid early detection of neurodevelopmental disorders. However, the integration of AI presents challenges such as data quality concerns, algorithmic bias, ethical concerns, and the need for robust regulatory frameworks. The authors argue that while AI offers significant opportunities, its implementation must be carefully managed to avoid over-reliance on technology and ensure equitable healthcare access. The paper concludes that the current state of AI in this field marks not an endpoint but a critical phase of growth and development, necessitating a balanced approach that combines innovation with ethical and practical considerations.

The effect of continuous electronic fetal monitoring on mode of delivery and neonatal outcome among low-risk laboring mothers at Debre Markos comprehensive specialized hospital, Northwest Ethiopia.

Electronic fetal heart rate monitoring (EFM) has been widely used in obstetric practice for over 40 years to improve perinatal outcomes. Its popularity is growing in Ethiopia and other sub-Saharan African countries to reduce high perinatal morbidity and mortality rates. However, its impact on delivery mode and perinatal outcomes in low-risk pregnancies remains controversial. This study aimed to assess the effect of continuous EFM on delivery mode and neonatal outcomes among low-risk laboring mothers at Debre Markos Comprehensive Specialized Hospital, Northwest Ethiopia. A prospective follow-up study was conducted from November 20, 2023, to January 10, 2024. All low-risk laboring mothers meeting the inclusion criteria were included. Data were collected via pretested structured questionnaires and observation, then analyzed using Epi-data 4.6 and SPSS. The incidences of cesarean delivery and continuous EFM were compared using the chi-squared test and Fisher's exact test. The study found higher rates of instrumental-assisted vaginal delivery (7% vs. 2.4%) and cesarean sections (16% vs. 2%) due to unsettling fetal heart rate patterns in the continuous EFM group compared to the intermittent auscultation group. However, there were no differences in immediate neonatal outcomes between the groups. When compared to intermittent auscultation with a Pinard fetoscope, the routine use of continuous EFM among low-risk laboring mothers was associated with an increased risk of cesarean sections and instrumental vaginal deliveries, without significantly improving immediate newborn outcomes. However, it is important to note that our study faced significant logistical constraints due to the limited availability of EFM devices, which influenced our ability to use EFM comprehensively. Given these limitations, we recommend avoiding the routine use of continuous EFM for low-risk laboring mothers to help reduce the rising number of operative deliveries, particularly cesarean sections. Our findings should be interpreted with caution, and further research with adequate resources is needed to draw definitive conclusions.

The benefit of active management in true knot of the umbilical cord: a retrospective study

PurposeTo compare perinatal outcomes between active and routine management in true knot of the umbilical cord (TKUC).MethodsA retrospective study of singletons born beyond 22 6/7 weeks with TKUC. Active management included weekly fetal heart rate monitoring(FHRM) ≥ 30 weeks and labor induction at 36–37 weeks. Outcomes in active and routine management were compared, including composite asphyxia-related adverse outcome, fetal death, labor induction, Cesarean section (CS) or Instrumental delivery due to non-reassuring fetal heart rate (NRFHR), Apgar5 score < 7, cord Ph < 7, neonatal intensive care unit (NICU) admission and more.ResultsThe Active (n = 59) and Routine (n = 1091) Management groups demonstrated similar rates of composite asphyxia-related adverse outcome (16.9% vs 16.8%, p = 0.97). Active Management resulted in higher rates of labor induction < 37 weeks (22% vs 1.7%, p < 0.001), CS (37.3% vs 19.2%, p = 0.003) and NICU admissions (13.6% vs 3%, p < 0.001). Fetal death occurred exclusively in the Routine Management group (1.8% vs 0%, p = 0.6).ConclusionCompared with routine management, weekly FHRM and labor induction between 36 and 37 weeks in TKUC do not appear to reduce neonatal asphyxia. In its current form, active management is associated with higher rates of CS, induced prematurity and NICU admissions. Labor induction before 37 weeks should be avoided.

Transcutaneous Discrimination of Fetal Heart Rate from Maternal Heart Rate: A Fetal Oximetry Proof-of-Concept.

Intrapartum care uses electronic fetal heart rate monitoring (EFHRM) for over 50years to indirectly assess fetal oxygenation. However, this approach has been associated with an increase in cesarean delivery rates and limited improvements in neonatal hypoxic outcome. To address these shortcomings, a novel transabdominal fetal pulse oximeter (TFO) is being developed to provide an objective measurement of fetal oxygenation. Previous studies have evaluated the performance of TFO on pregnant ewe. Building on the animal model, this study aims to determine whether TFO can successfully capture human fetal heart rate (FHR) signals during non-stress testing (NST) as a proof-of-concept. Eight ongoing pregnancies meeting specific inclusion criteria (18-40years old, singleton, and at least 36weeks' gestation) were enrolled with consent. Each study session was 15 to 20min long. Reference maternal heart rate (MHR) and FHR were obtained using finger pulse oximetry and cardiotocography for subsequent comparison. The overall root-mean-square error was 9.7BPM for FHR and 4.4 for MHR, while the overall mean-absolute error was 7.6BPM for FHR and 1.8 for MHR. Bland-Altman analysis displayed a mean bias ± standard deviation between TFO and reference of -3.9 ± 8.9BPM, with limits of agreement ranging from -21.4 to 13.6 BPM. Both maternal and fetal heart rate measurements obtained from TFO exhibited a p-value < 0.001, showing significant correlation with the reference. This proof-of-concept study successfully demonstrates that TFO can accurately differentiate maternal and fetal heart signals in human subjects. This achievement marks the initial step towards enabling fetal oxygen saturation measurement in humans using TFO.

Fetal premature atrial contractions: natural course, risk factors and adverse outcome.

Fetal premature atrial contractions (PAC) are usually benign but may be associated with congenital heart defect (CHD) and tachyarrhythmia, which in turn carry a risk of cardiac failure and fetal death. We aimed to explore the frequency of adverse outcome and to identify risk factors for tachyarrhythmia in pregnancies complicated by fetal PAC. This was a retrospective cohort study of fetuses diagnosed with PAC at two academic centers in Amsterdam, The Netherlands, between 2007 and 2022. Cases with a congenital anomaly and those with a prior diagnosis of CHD or other arrhythmias were excluded. M-mode and Doppler tracings were reanalyzed and the frequency of PAC was recorded. The incidence of the following adverse outcomes was examined: underlying CHD not identified at the 20-week fetal anomaly scan, tachyarrhythmia, other arrhythmia, administration of antiarrhythmic therapy and death. Risk factors for tachyarrhythmia were analyzed using odds ratios (OR). In 24.1% of 1439 referred cases, PAC resolved before confirmation at the fetal medicine unit (FMU). Of the 939 included cases with confirmed PAC, the total incidence of adverse outcome was 6.8% (64/939). CHD was diagnosed in 14 (1.5% (95% CI, 0.9-2.5%)) cases, of which eight were diagnosed prenatally and six postnatally. Compared with baseline, the incidence of CHD was higher in the presence of fetal PAC (OR, 1.8 (95% CI, 1.0-3.3); P = 0.034). Tachyarrhythmia occurred prenatally and/or postnatally in 32 (3.4%) cases, of which eight (25.0%) showed signs of cardiac failure, and in 23 (71.9%) cases, antiarrhythmic therapy was required. No cases of tachyarrhythmia led to fetal or infant death. Risk factors for tachyarrhythmia were PAC with short runs of supraventricular tachycardia (OR, 98.7), blocked PAC (OR, 30.3), PAC in bigeminy (OR, 21.8), frequent PAC (one per 5-10 beats) (OR, 6.9), signs of cardiac failure (OR, 14.2) and the presence of a foramen ovale aneurysm (OR, 5.0). PAC are generally benign and often resolve spontaneously. However, fetuses with an irregular heart rhythm should be referred for advanced ultrasonography, which should focus on classifying the type of PAC and risk of adverse outcome. When risk factors for tachyarrhythmia are identified, weekly fetal heart-rate monitoring is advised until resolution of the PAC. In the absence of risk factors, standard obstetric care may be sufficient, with additional instructions to report reduced fetal movements. Should tachyarrhythmia or cardiac failure develop, referral back to the FMU is indicated. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The iPREFACE score is useful for predicting fetal acidemia: A retrospective cohort study of 113 patients who underwent emergency cesarean section for non-reassuring fetal status during labor

The iPREFACE score may aid in predicting fetal acidemia and neonatal asphyxia in emergency cesarean and vaginal deliveries, which may improve labor management precision in the future. This study aimed to assess the score use of the iPREFACE as an objective indicator of the need for rapid delivery in cases of repeated abnormal waveforms without concurrent indications for immediate medical intervention during labor. This retrospective cohort study was conducted among term (37+ 0 days to 41+6 days) singleton pregnant women who underwent emergency cesarean delivery owing to a nonreassuring fetal status. The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-decision of emergency cesarean delivery score, calculated from a 30-minute cardiotocography waveform before the decision to perform emergency cesarean delivery, and the integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-removal of cardiotocography transducer score, calculated from a 30-minute cardiotocography waveform before cardiotocography transducer removal, were employed. The primary outcome was the assessment of the predictive ability of these scores for fetal acidemia, whereas the secondary outcomes were differences in umbilical artery blood gas findings and postnatal outcomes between the 2 groups, divided by the cutoff values of the integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-removal of cardiotocography score. The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-decision of emergency cesarean delivery and integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-removal of cardiotocography transducer scores demonstrated the capability to predict an umbilical artery blood pH of <7.2. The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-decision of emergency cesarean delivery and -removal of cardiotocography transducer score, with cutoff values of 37 and 46 points, respectively, exhibited an area under the receiver operating characteristic curve of 0.82 and 0.87, respectively. The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-removal of cardiotocography transducer group with ≥46 points had higher incidence rates of an umbilical cord artery blood pH of <7.2, <7.1, and <7.0 and neonatal intensive care unit admissions for neonatal asphyxia. The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring, derived from cardiotocography during an emergency cesarean delivery, may enable clinicians to predict fetal acidemia in cases of nonreassuring fetal status. Improved prediction of fetal acidemia and facilitation of timely intervention hold promise for enhancing the outcomes of mothers and newborns during childbirth. Prospective studies are warranted to establish precise cutoff values and to validate the clinical application of these scores.

Computer Vision for Identification of Increased Fetal Heart Variability in Cardiotocogram

Introduction: Increased fetal heart rate variability (IFHRV), defined as fetal heart rate (FHR) baseline amplitude changes of >25 beats per minute with a duration of ≥1 min, is an early sign of intrapartum fetal hypoxia. This study evaluated the level of agreement of machine learning (ML) algorithms-based recognition of IFHRV patterns with expert analysis. Methods: Cardiotocographic recordings and cardiotocograms from 4,988 singleton term childbirths were evaluated independently by two expert obstetricians blinded to the outcomes. Continuous FHR monitoring with computer vision analysis was compared with visual analysis by the expert obstetricians. FHR signals were graphically processed and measured by the computer vision model labeled SALKA. Results: In visual analysis, IFHRV pattern occurred in 582 cardiotocograms (11.7%). Compared with visual analysis, SALKA recognized IFHRV patterns with an average Cohen’s kappa coefficient of 0.981 (95% CI: 0.972–0.993). The sensitivity of SALKA was 0.981, the positive predictive rate was 0.822 (95% CI: 0.774–0.903), and the false-negative rate was 0.01 (95% CI: 0.00–0.02). The agreement between visual analysis and SALKA in identification of IFHRV was almost perfect (0.993) in cases (N = 146) with neonatal acidemia (i.e., umbilical artery pH <7.10). Conclusions: Computer vision analysis by SALKA is a novel ML technique that, with high sensitivity and specificity, identifies IFHRV features in intrapartum cardiotocograms. SALKA recognizes potential early signs of fetal distress close to those of expert obstetricians, particularly in cases of neonatal acidemia.

PCA-Based Preprocessing for Clustering-Based Fetal Heart Rate Extraction in Non-Invasive Fetal Electrocardiograms

Non-invasive fetal electrocardiography (NI-ECG) is based on the acquisition of signals from electrodes on the mother’s abdominal surface. This abdominal ECG (aECG) signal consists of the maternal ECG (mECG) along with the fetal ECG (fECG) and other noises and artifacts. These records allow the acquisition of valuable and reliable information that helps ensure fetal well-being during pregnancy. This paper proposes a procedure based on principal component analysis (PCA) to obtain a single-channel master abdominal ECG record that can be used as input to fetal heart rate extraction techniques. The new procedure requires three main processing stages: PCA-based analysis for fECG-component extraction, polarity test, and curve fitting. To show the advantages of the proposal, this PCA-based method has been used as the feeding stage to a previously developed clustering-based method for single-channel aECG fetal heart rate monitoring. The results obtained for a set of real abdominal ECG recordings from annotated public aECG databases, the Abdominal and Direct Fetal ECG Database and the Challenge 2013 Training Set A, show improved efficiency in fetal heart rate extraction and illustrate the benefits derived from the use of such a master abdominal ECG channel. This allows us to achieve proper fetal heart rate monitoring without the need for manual inspection and selection of channels to be processed, while also allowing us to analyze records that would have been discarded otherwise.

Is it time to end the use of base deficit for fetal well-being assessment?

Authors have expressed reservations regarding the use of base deficit measured in umbilical artery blood samples to assess fetal well-being during the course of labor and to predict neonatal neurologic morbidity. Despite its integration into clinical practice for more than 50 years, obstetricians and maternal-fetal medicine specialists may not realize that this marker has significant limitations in accurately identifying neonatal metabolic acidosis as a proxy for fetal well-being. In brief, there are 2 large families of base deficit, namely whole blood and extracellular fluid. Both rely on equations that use normal adult acid-base characteristics (pH 7.40 and partial CO2 pressure of 40 mm Hg) that overlook the specificity of the normal in utero acid-base status of pH 7.27 and partial CO2 pressure of 54 mm Hg. In addition, it ignores the unique characteristic of the in utero fetal response to acute hypoxia. The dependence on placental circulation for CO2 elimination may lead to extremely high values (up to 130 to 150 mm Hg) during hypoxic events, a phenomenon that is absent in adults with acute metabolic acidosis who can hyperventilate. The dispute over if to include a correction for high partial CO2 pressure in the bicarbonate estimation, as presented in the Great Trans-Atlantic Debates, remains unresolved. The key constants computed for adult acid-base physiology in the current base deficit algorithms, without accounting for the impact of high partial CO2 pressure or other fetal characteristics of buffering capacity (eg, differences in body water content composition, plasma protein, and hemoglobin attributes), may lead to an overestimation of metabolic acidosis, especially in newborns who are experiencing hypercarbia during the early stages of the hypoxic response. These unrecognized limitations impact the base deficit results and may mislead clinicians on fetal well-being assessments when discussing the management of fetal heart rate monitoring and neonatal outcomes. Based on our arguments, we believe that it is prudent to consider an alternative to base deficit for drawing conclusions regarding fetal well-being during the course of birth management. We propose a marker specifically related to the newborn acid-base physiology--the neonatal eucapnic pH correction. This marker can be added to arterial cord blood gas analysis, and we have described how to interpret it as a marker of neonatal metabolic acidosis.

Hybrid-FHR: a multi-modal AI approach for automated fetal acidosis diagnosis

BackgroundIn clinical medicine, fetal heart rate (FHR) monitoring using cardiotocography (CTG) is one of the most commonly used methods for assessing fetal acidosis. However, as the visual interpretation of CTG depends on the subjective judgment of the clinician, this has led to high inter-observer and intra-observer variability, making it necessary to introduce automated diagnostic techniques.MethodsIn this study, we propose a computer-aided diagnostic algorithm (Hybrid-FHR) for fetal acidosis to assist physicians in making objective decisions and taking timely interventions. Hybrid-FHR uses multi-modal features, including one-dimensional FHR signals and three types of expert features designed based on prior knowledge (morphological time domain, frequency domain, and nonlinear). To extract the spatiotemporal feature representation of one-dimensional FHR signals, we designed a multi-scale squeeze and excitation temporal convolutional network (SE-TCN) backbone model based on dilated causal convolution, which can effectively capture the long-term dependence of FHR signals by expanding the receptive field of each layer’s convolution kernel while maintaining a relatively small parameter size. In addition, we proposed a cross-modal feature fusion (CMFF) method that uses multi-head attention mechanisms to explore the relationships between different modalities, obtaining more informative feature representations and improving diagnostic accuracy.ResultsOur ablation experiments show that the Hybrid-FHR outperforms traditional previous methods, with average accuracy, specificity, sensitivity, precision, and F1 score of 96.8, 97.5, 96, 97.5, and 96.7%, respectively.ConclusionsOur algorithm enables automated CTG analysis, assisting healthcare professionals in the early identification of fetal acidosis and the prompt implementation of interventions.

Evaluation and patient experience of wireless noninvasive fetal heart rate monitoring devices.

In clinical practice, fetal heart rate monitoring is performed intermittently using Doppler ultrasound, typically for 30 minutes. In case of a non-reassuring heart rate pattern, monitoring is usually prolonged. Noninvasive fetal electrocardiography may be more suitable for prolonged monitoring due to improved patient comfort and signal quality. This study evaluates the performance and patient experience of four noninvasive electrocardiography devices to assess candidate devices for prolonged noninvasive fetal heart rate monitoring. Non-critically sick women with a singleton pregnancy from 24 weeks of gestation were eligible for inclusion. Fetal heart rate monitoring was performed during standard care with a Doppler ultrasound device (Philips Avalon-FM30) alone or with this Doppler ultrasound device simultaneously with one of four noninvasive electrocardiography devices (Nemo Fetal Monitoring System, Philips Avalon-Beltless, Demcon Dipha-16 and Dräger Infinity-M300). Performance was evaluated by: success rate, positive percent agreement, bias, 95% limits of agreement, regression line, root mean square error and visual agreement using FIGO guidelines. Patient experience was captured using a self-made questionnaire. A total of 10 women were included per device. For fetal heart rate, Nemo performed best (success rate: 99.4%, positive percent agreement: 94.2%, root mean square error 5.1 BPM, bias: 0.5 BPM, 95% limits of agreement: -9.7 - 10.7 BPM, regression line: y = -0.1x + 11.1) and the cardiotocography tracings obtained simultaneously by Nemo and Avalon-FM30 received the same FIGO classification. Comparable results were found with the Avalon-Beltless from 36 weeks of gestation, whereas the Dipha-16 and Infinity-M300 performed significantly worse. The Avalon-Beltless, Nemo and Infinity-M300 closely matched the performance of the Avalon-FM30 for maternal heart rate, whereas the performance of the Dipha-16 deviated more. Patient experience scores were higher for the noninvasive electrocardiography devices. Both Nemo and Avalon-Beltless are suitable devices for (prolonged) noninvasive fetal heart rate monitoring, taking their intended use into account. But outside its intended use limit of 36 weeks' gestation, the Avalon-Beltless performs less well, comparable to the Dipha-16 and Infinity-M300, making them currently unsuitable for (prolonged) noninvasive fetal heart rate monitoring. Noninvasive electrocardiography devices appear to be preferred due to greater comfort and mobility.

Correlation between total deceleration area in CTG records and cord blood pH in pregnancies with IUGR.

Fetal cardiotocography is the most common method to assess fetal well-being during labor. Nevertheless, its predictive ability for acidemia is limited, both in low-risk and high-risk pregnancies (Nelson et al. in N Engl J Med 334: 613-9, 1996; Rinciples P et al. in Health and Human Development Workshop Report on Electronic Fetal Monitoring : Update on Definitions. no. 2007, 510-515, 2008), especially in high-risk pregnancies, such as those complicated by growth restriction. In this study we aim examine the association between deceleration and acceleration areas and other measure of fetal heart rate in intrapartum fetal monitoring and neonatal arterial cord blood pH in pregnancies complicated by growth restriction. A retrospective cohort study of 100 deliveries complicated by growth restriction, delivered during 2018, was conducted. Known major fetal anomalies, non-vertex presentation and elective cesarean deliveries were excluded. Total deceleration and acceleration areas were calculated as the sum of the areas within the deceleration and acceleration, respectively. In deliveries complicated by growth restriction, cord blood pH is significantly associated with total deceleration area (p = 0.05) and correlates with cumulative duration of the decelerations (Spearman's rank -0.363, p < 0.05), and total acceleration area (-0.358, p < 0.05). By comparing the cord blood pH in deliveries with a total deceleration area that was above and below the median total deceleration area, we demonstrated a significant difference between the categories. Cord blood pH significantly correlates with total deceleration area and other fetal monitoring characteristics in neonates with growth restriction. Future studies using real-time, machine-learning based techniques of fetal heart rate monitoring, may provide population specific threshold values that will support bedside clinical decision making and perhaps achieve better outcomes.