Association between Fetal Heart Rate Monitoring during Labor and Neonatal Acidosis in Full-Term Newborns: A Retrospective Multicenter Cohort Study

Introduction: Fetal heart rate monitoring during labor is used to study fetal well-being and predict neonatal acidosis of newborn. Fetal heart rate monitoring is analyzed by the obstetrical team and categorized according to the FIGO guidelines. An important limitation of this diagnostic tool is an inter- and intra-observer variability, leading to subjective cardiotocography interpretation and classification. Our objective was to study the association between the categories of fetal heart rate analysis (according to FIGO classification) and neonatal acidosis of full-term newborns. Study design: This is a multicenter retrospective cohort study conducted between 2014 and 2018 in the Grand-Est region. We searched and included retrospectively children hospitalized in a pediatric intensive care unit in one of the participating hospitals with an ICD-10 coding type “P91.6” corresponding to “Hypoxic Ischemic Encephalopathy”. Maternal, pregnancy, delivery, and newborn characteristics were collected and compared by univariate logistic regression with multiple imputation. Odds Ratio and 95% confidence intervals (CI) were calculated using the model and presented. Multiple imputation with m = 100 imputations was tested, using Rubin rules to combine the results. Results: 55 patients were included in the study. Fetal heart rate tracings classified in Category 3 as “pathological” according to FIGO guidelines were significantly associated with an increased risk of severe neonatal acidosis. Late decelerations and bradycardia during labor were associated with severe neonatal acidosis. Conclusion: Severe neonatal acidosis may be suspected by interpretation of fetal heart rate during labor. Fetal bradycardia and late decelerations are predictive of the severity of neonatal acidosis. This study emphasizes the need to screen severe neonatal acidosis and allows the identification of populations most at risk. Repeated team training and upgrading of fetal heart rate study would further reduce the incidence of neonatal acidosis.

The Signal Extraction of Fetal Heart Rate Based on Wavelet Transform and BP Neural Network

This paper briefly introduces the collection and recognition of bio-medical sig nals, designs the method to collect FM signals. A detailed discussion on the sys tem hardware, structure and functions is also given. Under LabWindows/CVI,the ha rdware and the driver do compatible, the hardware equipment work properly active ly. The paper adopts multi threading technology for real-time analysis and make s use of latency time of CPU effectively, expedites program reflect speed, impro ve s the program to perform efficiency. One threading is collecting data; the other threading is analyzing data. Using the method, it is broaden to analyze the sig nal in real-time. Wavelet transform to remove the main interference in the FM a nd by adding time-window to recognize with BP network; Finally the results of c ollecting signals and BP networks are discussed.8 pregnant women’s signals of F M were collected successfully by using the sensor. The correct of BP network rec ognition is about 83.3% by using the above measure.

Unexplained fetal tachycardia:A case report

BACKGROUND This study aimed to explore the possible etiology and treatment of severe fetal tachycardia in the absence of organic disease and provide a reference for clinical management of severe fetal tachycardia.CASE SUMMARY A 29-year-old pregnant woman,with a gravidity 1 parity 0,presented with a fetal heart rate(FHR)of 243 beats per minute during a routine antenatal examination at 31+2 wk of gestation.Before termination of pregnancy at 38 wk of gestation,the FHR repeatedly showed serious abnormalities,lasting more than 30 min.However,the pregnant woman and the fetus had no clinical symptoms,and repeated examination revealed no organic lesions.The mother and the baby were regularly followed up.CONCLUSION This was a case of severe fetal tachycardia with no organic lesions and management based on clinical experience.

Imperative for improvements and international convergence of intrapartum fetal monitoring: A bird's eye view

Intrapartum fetal monitoring has been criticized for the lack of evidence of improvement in fetal outcome despite causing increased operative intervention. Paradoxically, cardiotocography （CTG） has been a major driver for litigation for neonatal neurological injury. This analytical review tries to explore why extensive clinical studies and trials over 50 years have failed to demonstrate or bring about signifcant improvement in intrapartum fetal monitoring. There seems a need for significant reform. International congruence on most aspects of CTG interpretation [defnitions of fetal heart rate （FHR） parameters, CTG recording speed, 3-tier systems, etc .] is highly desirable to facilitate future meaningful clinical studies, evaluation and progress in this field. The FHR changes are non-specific and poor surrogate for fetal well-being. As a compromise for maintaining low false-negative results for fetal acidemia, a high false-positive value may have to be accepted. The need for redefning the place of adjuvant tests of fetal well-being like fetal blood sampling or fetal electrocardiography （ECG） is discussed. The FHR decelerations are often deterministic （center-stage） in CTG interpretation and 3-tier categorization. It is discussed if their scientifc and physiological classifcation （avoiding framing and confirmation biases） may be best based on time relationship to uterine contractions alone. This may provide a more sound foundation which could improve the reliability and further evolution of 3-tier systems. Results of several trials of fetal ECG （STAN） have been inconclusive and a need for a fresh approach or strategy is considered. It is hoped that the long anticipated Computer-aided analysis of CTG will be more objective and reliable （overcome human factors） and will offer valuable support or may eventually replace visual CTG interpretation. In any case, the recording and archiving all CTGs digitally and testing cord blood gases routinely in every delivery would be highly desirable for future research. This would facilitate well designed retrospective studies which can be very informative especially when prospective randomised controlled trials are often diffcult and resource-intensive.

The Efficacy of In-Phase and Quadrature Demodulation in Electronic Fetal Heart Rate Monitoring During Labor

Objective:To investigate the efficacy of in-phase and quadrature(IQ)demodulation in electronic fetal heart rate monitoring(EFM)to reduce false reports of fetal heart rate(FHR)doubling or halving.Methods:This is a prospective cohort study.A total of 263 full-term pregnant women who delivered at Peking University Shenzhen Hospital between August 2019 and July 2020 were prospectively enrolled in the study.FHR monitoring began when the cervix was dilated to 2-3 cm and continued until delivery.Raw fetal Doppler audio signals and internal and external cardiotocography curves from internal electrode monitoring,EFM with conventional demodulation(external),and EFM with IQ demodulation(external)were acquired to compare FHR doubling and halving time.In cohort 1,FHR was compared between IQ demodulation and conventional demodulation.In cohort 2,FHR was compared between IQ demodulation,conventional demodulation,and internal FHR monitoring.Count data were statistically analyzed using the Chi-squared test,and measurement data were statistically analyzed usingt-test for correlation coefficients,and Bland-Altman analysis for concordance ranges.Results:To compare IQ demodulation and conventional demodulation,225 pregnant women were monitored for a total of 835,870 seconds.The beat-to-beat interval of FHRs in raw fetal Doppler audio signals was used as the reference.The results showed a doubling time of 3401 seconds(0.407%,3401/835,870)and a halving time of 2918 seconds(0.349%,2918/835,870)with conventional demodulation,compared to 241 seconds(0.029%,241/835,870)and 589 seconds(0.070%,589/835,870),respectively,with IQ demodulation.IQ demodulation reduced FHR doubling by approximately 93%(3160/3401)and FHR halving by approximately 80%(2329/2918)compared to conventional demodulation(P<0.01).Conclusion:EFM with IQ demodulation significantly reduces false FHR doubling and halving,with an efficacy similar to that of internal FHR monitoring.

CTGNet: Automatic Analysis of Fetal Heart Rate from Cardiotocograph Using Artificial Intelligence

Objective:This study investigates the efficacy of analyzing fetal heart rate(FHR)signals based on Artificial Intelligence to obtain a baseline calculation and identify accelerations/decelerations in the FHR through electronic fetal monitoring during labor.Methods:A total of 43,888 cardiotocograph(CTG)records of female patients in labor from January 2012 to December 2020 were collected from the NanFang Hospital of Southern Medical University.After filtering the data,2341 FHR records were used for the study.The ObVue fetal monitoring system,manufactured by Lian-Med Technology Co.Ltd.,was used to monitor the FHR signals for these pregnant women from the beginning of the first stage of labor to the end of delivery.Two obstetric experts together annotated the FHR signals in the system to determine the baseline as well as accelerations/decelerations of the FHR.Our cardiotocograph network(CTGNet)as well as traditional methods were then used to automatically analyze the baseline and acceleration/deceleration of the FHR signals.The results of calculations were compared with the annotations provided by the obstetric experts,and ten-fold cross-validation was applied to evaluate them.The root-mean-square difference(RMSD)between the baselines,acceleration F-measure(Acc.F-measure),deceleration F-measure(Dec.F-measure),coefficient of synthetic inconsistency(SI)and the morphological analysis discordance index(MADI)were used as evaluation metrics.The data were analyzed by using a pairedt-test.Results:The proposed CTGNet was superior to the best traditional method,proposed by Mantel,in terms of the RMSD.BL(1.7935±0.8099vs.2.0293±0.9267,t=-3.55,P=0.004),Acc.F-measure(86.8562±10.9422vs.72.2367±14.2096,t=12.43,P<0.001),Dec.F-measure(72.1038±33.2592vs.58.5040±38.0276,t=4.10,P<0.001),SI(34.8277±20.9595vs.54.8049±25.0265,t=-9.39,P<0.001),and MADI(3.1741±1.9901vs.3.7289±2.7253,t=-2.74,P=0.012).The proposed CTGNet thus had significant advantages over the best traditional method on all evaluation metrics.Conclusion:The proposed Artificial Intelligence-based method CTGNet delivers good performance in terms of the automatic analysis of FHR based on cardiotocograph data.It promises to be a key component of smart obstetrics systems of the future.

Oxytocin Abuse and Postpartum Hemorrhage

Among the most consolidated dogmas in obstetrics, we have the essential role of oxytocin during: labor by regulating, consolidating uterine contractions, by supporting the expulsive efforts of the patient during childbirth and after childbirth by preventing postpartum hemorrhage. But what challenged us to conduct our study is the large and increasing number of surgical operations for postpartum hemorrhage in patients who received oxytocin during labor. We assumed that the generalization use of oxytocin in all patients during labor is probably responsible of this increasing rate of incidents. To verify this assumption, we carried out a prospective randomized comparative study, involving 3990 pregnant patients admitted at the start of labor at term, with no contraindication for giving birth by normal ways, during a period of 10 months (January-October 2022). The patients have been divided into 2 groups. The first group comprises 1991 patients who were placed on admission on a glucose serum infusion with 4 ampoules of a non-anticholinergic musculotropic antispasmodic: “Hydrated phloroglucinol + trimethylphloroglucinol” (Each ampoule contains 40 mg of hydrated phloroglucinol and 0.04 mg of trimethylphloroglucinol) instead of receiving oxytocin during the active phase of their labor and a second group consisting of 1999 patients who received oxytocin during the active phase of their labor. The results were very surprising and contrary to the already consolidated evidence in our specialty. Indeed, the rate of postpartum hemorrhages was 10 patients (0.5%) in the 1st group vs 30 patients (1.5%) in the 2nd group, 9 patients (0.4%) presented fetal heart rate abnormalities in the 1st group vs 90 (4.5%) in the 2nd group, 8 cases (0.4%) of dynamic dystocia in the 1st group vs 132 cases (6.6%) in the 2nd group and 99 caesareans (5%) in the 1st group vs 299 (15%) in the 2nd group. Against all expectations the results were very surprising, with more details in the article.

Antenatal Noninvasive Fetal Electrocardiography:A Literature Review

Fetal heart rate(FHR)monitoring is one of the central parts of obstetric care.Ultrasound-based technologies such as cardiotocography(CTG)remain the most common method for FHR monitoring.The CTG’s limitations,including subjective interpretation,high interobserver variability,and the need for skilled professionals,led to the development of computerized CTG(cCTG).While cCTG demonstrated advantages,its superiority over visual interpretation remains inconclusive.This has prompted the exploration of alternatives like noninvasive fetal electrocardiography(NIFECG).This review explores the landscape of antenatal FHR monitoring and the need for remote FHR monitoring in a patient-centered care model.Additionally,FHR monitoring needs to evolve from the traditional approach to incorporate artificial intelligence and machine learning.The review underscores the importance of aligning fetal monitoring with modern healthcare,leveraging artificial intelligence algorithms for accurate assessments,and enhancing patient engagement.The physiology of FHR variability(FHRV)is explained emphasizing its significance in assessing fetal well-being.Other measures of FHRV and their relevance are described.It delves into the promising realm of NIFECG,detailing its history and recent technological advancements.The potential advantages of NIFECG are objective FHR assessment,beat-to-beat variability,patient comfort,remote prolonged use,and less signal loss with increased maternal body mass index.Despite its promise,challenges such as signal loss must be addressed.The clinical application of NIFECG,its correlation with cCTG measures,and ongoing technological advancements are discussed.In conclusion,this review explores the evolution of antenatal FHR monitoring,emphasizing the potential of NIFECG in providing reliable,home-based monitoring solutions.Future research directions are outlined,urging longitudinal studies and evidence generation to establish NIFECG’s role in enhancing fetal well-being assessments during pregnancy.