Uterine Contraction Monitoring Research Articles

IoT-based Pregnant Mother Contraction Monitoring System Design

Pregnancy is an important stage in a woman's life that requires special monitoring and care to ensure the well-being of both mother and fetus. The presence of uterine contractions is an im-portant indicator of imminent labour, and prompt monitoring is essential to spot difficulties and ensure a safe delivery. This study aims to track contractions in pregnant women to improve pre-natal and labour care. Real-time monitoring, recording and analysis of uterine contractions. This research is a type of RD research with the ADDIE model (Analysis, Design, Development, Implementation, and Evaluation. The result of this tool is that it can precisely track contraction activity and send information to the IoT network. Through an easy-to-use mobile app, this in-formation can be accessed by medical staff caring for pregnant women and pregnant women themselves. To provide continuous monitoring, provide early notification of alarming changes, and facilitate rapid medical response, this monitoring system utilizes IoT technology. This can ease the burden on medical institutions, lower the possibility of difficulties during labour, and provide a sense of security for pregnant women. As an innovative and effective tool, the Inter-net of Things-based Maternal Contraction Monitoring System is anticipated to improve prenatal and delivery healthcare, reduce maternal and infant mortality, and monitor contractions in preg-nant women. The healthcare of pregnant women around the world could be significantly im-proved with the successful implementation of this approach.

Parturition Detection Using Oxytocin Secretion Level and Uterine Muscle Contraction Intensity

The "Parturition Detection Sensor Belt," also known as the "Labor Pain Detection Sensor Belt," represents a novel advancement in maternal health monitoring. "Parturition Detection Sensor Belt" designed to simultaneously predict oxytocin levels and monitor uterine muscle contractions. This innovative system combines real-time prediction of oxytocin levels and simultaneous monitoring of uterine muscle contractions to provide a comprehensive solution for parturition detection. By integrating cutting-edge sensor technology and deep learning algorithms, the system offers precise, non-invasive monitoring during labor. The oxytocin level predictions aid in understanding maternal well-being, while the real-time uterine muscle contraction monitoring ensures early detection of labor progression. This interdisciplinary approach leverages advancements in biomedical engineering and data analysis, holding promise for improving the safety and care of expectant mothers. The "Parturition Detection Sensor Belt" has the potential to revolutionize the field of obstetrics by offering a versatile tool for healthcare providers, enhancing maternal health, and facilitating data-driven research in this critical domain. A correlation is developed between oxytocin release and muscle contraction which turns out to be nearly 0,899836. This infers that the two factors that we are considering as important parameters are having a strong association with each other

Method for Simultaneous Monitoring of Uterine Contractions and Abdominal Pushing in a Childbirth

Method for Simultaneous Monitoring of Uterine Contractions and Abdominal Pushing in a Childbirth

Experiences with intrapartum fetal monitoring in the Netherlands: A survey study

IntroductionWorldwide, cardiotocography is used for continuous monitoring of fetal heart rate (FHR) and uterine contractions during labour. Different methods for FHR registration and registration of contractions are available. Literature about the frequency of use of different fetal monitoring methods is lacking. ObjectiveTo evaluate the use of and preferences for fetal monitoring methods for intrapartum fetal monitoring among Dutch obstetric care providers. Study designBetween October and November 2020 the Dutch Society of Obstetrics and Gynaecology sent an email invitation to all secondary care midwives and gynaecologists (in training) in the Netherlands to complete an online survey regarding the use and personal experience with fetal monitoring methods. The survey mainly consisted of multiple choice questions. Descriptive statistics are reported. Continuous variables were presented as median with interquartile ranges (IQR). Categorical variables were expressed as numbers with percentages. ResultsThe response rate was 29 % (n/N = 510/1748). All Dutch hospitals were represented. The respondents estimated the use of fetal scalp electrode (FSE) at 71 % (IQR 58–85 %) of deliveries. The most common indication for use of the FSE was inadequate external FHR registration (94 %). More than half (54 %) of the respondents reported to use intrauterine pressure catheter with an estimated use of 5 % (IQR 2–8 %) of deliveries. The most common indication for use of intrauterine pressure catheter was inadequate external contraction registration (75 %). The use of ST-analysis was reported in 25 % of the respondents with an estimated use of 60 % (IQR 30–72 %) of deliveries. Almost all respondents (99 %) reported to use fetal blood sampling with an estimated use of 15 % (IQR 10–23 %) of deliveries. Ninety percent of respondents would prefer a valid and reliable external monitoring technique during labour. Thirty-one percent of respondents assume that external fetal monitoring with non-invasive fetal electrocardiography and electrohysterography will become standard care within the next 5 years. ConclusionsCurrently, the FSE is the most used technique for FHR monitoring during labour in the Netherlands. The most common indication for use of FSE is inadequate external FHR registration. Obstetric care providers would prefer a non-invasive external registration method that provides reliable data.

COVID-19 Infection in Pregnancy: A Review.

Coronavirus disease 2019 (COVID-19), which is a highly contagious viral illness caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has had a catastrophic effect on the world's demographics, resulting in more than 3.8 million deaths worldwide and establishing itself as the most serious global health crisis since the 1918 influenza pandemic. Several questions remain unanswered regarding the effects of COVID-19 disease during pregnancy. Although most infections are mild in high-risk populations, the severe disease frequently leads to intubation, intensive care unit admission, and, in some cases, death. Hormonal and physiological changes in the immune and respiratory systems, cardiovascular function, and coagulation may affect the progression of COVID-19 disease in pregnancy. However, the consequences of coronavirus infection on implantation, fetal growth and development, labor, and newborn health have yet to be determined, and, consequently, a coordinated global effort is needed in this respect. Principles of management concerning COVID-19 in pregnancy include early isolation, aggressive infection control procedures, oxygen therapy, avoidance of fluid overload, consideration of empiric antibiotics (secondary to bacterial infection risk), laboratory testing for the virus and co-infection, fetal and uterine contraction monitoring, prevention, and / or treatment of thromboembolism early mechanical ventilation for progressive respiratory failure, individualized delivery planning, and a team-based approach with multispecialty consultations. This review focuses on COVID-19 during pregnancy, its management, and the area where further investigations are needed to reduce the risk to mothers and their newborns.

Tocodynamometry in canine uterine inertia

Early detection of uterine inertia is very crucial for the life of the foetus as well as that of the dam. Suitable methods for early detection of uterine inertia are lacking in canines compared to humans.Non-invasivetocodynamometry is a promising method, which is widely used in humans for the management of uterine inertia.In the present study non-invasive uterine contraction monitoring using the tocodynamometry was performed in dogs with Complete Primary Uterine Inertia (CPUI) and Partial Primary Uterine Inertia (PPUI), as well as in control animals with the Foetal Cause of Dystocia (FCD).In all the dogs belonging to CPUI and PPUI, the contractions were mild and infrequent with force near to the baseline, i.e., less than 15 mm of Hg. There were no reflex contractions in response to the feathering of the vaginal wall in a majority of dogs belonging to these two groups. In the FCD group, there were strong and frequent contractions lasting for two to three minutes with contraction force above 15mm of Hg, reaching up to 30-40 mm of Hg. Those dogs with less than 15 mm of Hg pressure and feeble or infrequent contractions without delivery for more than 30 min, could be considered as uterine inertia and suitable therapeutic options could be considered judiciously. Tocodynamometry was found to be an effective tool for the early detection of uterine inertia,whichhelped arriving at a quick judicious decision which is pertinent for better foetal and maternal survival.

A Novel Hybrid Model For Automated Analysis Of Cardiotocograms Using Machine Learning Algorithms

In this study, a new hybrid model was presented for the prediction of fetal state from fetal heart rate (FHR) and the uterine contraction (UC) signals obtained from cardiotocogram (CTG) recordings. CTG monitoring of FHR and uterine contractions during pregnancy and delivery provides information on the physiological status of the fetus to identify hypoxia. Accurate information from these records can be used to estimate the pathological condition of the fetus. Thus, it allows early intervention by reporting any irreversible negative condition in the fetus. In this study, due to the importance of this subject, a new hybrid model was developed which can perform high rate accurate diagnosis using Machine Learning (ML) algorithms. In the hybrid model, 4 different ML algorithms (k Nearest Neighbors (k-NN), Decision Tree (DT), Naive Bayes (NB) and Support Vector Machine (SVM)) were used. While the diagnosis without the hybrid model was low, the improved hybrid model increased the accuracy by 34%. As a result of this hybrid model, 100% success was achieved for classification, test success, Accuracy, Sensitivity and Specificity with NB and DT ML algorithms.

Novel uterine contraction monitoring to enable remote, self-administered nonstress testing

The serial fetal monitoring recommended for women with high-risk pregnancies places a substantial burden on the patient, often disproportionately affecting underprivileged and rural populations. A telehealth solution that can empower pregnant women to obtain recommended fetal surveillance from the comfort of their own home has the potential to promote health equity and improve outcomes. We have previously validated a novel, wireless pregnancy monitor that can remotely capture fetal and maternal heart rates. However, such a device must also detect uterine contractions if it is to be used to robustly conduct remote nonstress tests. This study aimed to describe and validate a novel algorithm that uses biopotential and acoustic signals to noninvasively detect uterine contractions via a wireless pregnancy monitor. A prospective, open-label, 2-center study evaluated simultaneous detection of uterine contractions by the wireless pregnancy monitor and an intrauterine pressure catheter in women carrying singleton pregnancies at ≥32 0/7 weeks' gestation who were in the first stage of labor (ClinicalTrials.gov Identifier: NCT03889405). The study consisted of a training phase and a validation phase. Simultaneous recordings from each device were passively acquired for 30 to 60 minutes. In a subset of the monitoring sessions in the validation phase, tocodynamometry was also deployed. Three maternal-fetal medicine specialists, blinded to the data source, identified and marked contractions in all modalities. The positive agreement and false-positive rates of both the wireless monitor and tocodynamometry were calculated and compared with that of the intrauterine pressure catheter. A total of 118 participants were included, 40 in the training phase and 78 in the validation phase (of which 39 of 78 participants were monitored simultaneously by all 3 devices) at a mean gestational age of 38.6 weeks. In the training phase, the positive agreement for the wireless monitor was 88.4% (1440 of 1692 contractions), with a false-positive rate of 15.3% (260/1700). In the validation phase, using the refined and finalized algorithm, the positive agreement for the wireless pregnancy monitor was 84.8% (2722/3210), with a false-positive rate of 24.8% (897/3619). For the subgroup who were monitored only with the wireless monitor and intrauterine pressure catheter, the positive agreement was 89.0% (1191/1338), with a similar false-positive rate of 25.4% (406/1597). For the subgroup monitored by all 3 devices, the positive agreement for the wireless monitor was significantly better than for tocodynamometry (P<.0001), whereas the false-positive rate was significantly higher (P<.0001). Unlike tocodynamometry, whose positive agreement was significantly reduced in the group with obesity compared with the group with normal weight (P=.024), the positive agreement of the wireless monitor did not vary across the body mass index groups. This novel method to noninvasively monitor uterine activity, via a wireless pregnancy monitoring device designed for self-administration at home, was more accurate than the commonly used tocodynamometry and unaffected by body mass index. Together with the previously reported remote fetal heart rate monitoring capabilities, this added ability to detect uterine contractions has created a complete telehealth solution for remote administration of nonstress tests.

Noninvasive monitoring of uterine electrical activity among patients with obesity: a new external monitoring device

Tocodynamometry is a common, noninvasive tool used to measure contraction frequency; however, its utility is often limited in patients with obesity. An intrauterine pressure catheter provides a more accurate measurement of uterine contractions but requires ruptured membranes, limiting its utility during early latent labor. Electrical uterine myography has shown promise as a noninvasive contraction monitor with efficacy similar to that of the intrauterine pressure catheter; however, its efficacy has not been widely studied in the obese population. This study aimed to validate the accuracy of electrical uterine myography by comparing it with tocodynamometry and intrauterine pressure catheters among laboring patients with obesity. This was a prospective observational study from February 2017 to April 2018 of patients with obesity, aged 18 years or older, who were admitted to the labor unit with viable singleton pregnancies and no contraindications for electromyography. Patients were monitored simultaneously with electrical myography and tocodynamometry or intrauterine catheter for more than 30 minutes. Two blinded obstetricians reviewed the tracings. The outcomes of interest were continuous and interpretable tracing, number of contractions, and timing and duration of contractions, interpreted as point estimates and associated 95% confidence intervals. A total of 110 patients were enrolled (65 tocodynamometry, 55 intrauterine catheter). Electrical myography was significantly more interpretable during a 30-minute tracing (P=.001) and detected 39% more contractions than tocodynamometry (P<.0001; 95% confidence interval, 23%-57%), whereas there was no difference in the interpretability of tracings or number of contractions between electrical myography and an intrauterine catheter (P=.16; 95% confidence interval, -0.19 to 1.19). Patients who underwent simultaneous monitoring preferred the electrical myography device over tocodynamometry. Electrical uterine myography is superior to tocodynamometry in the detection of intrapartum uterine contraction monitoring and comparable with internal contraction monitoring.

383 Evaluating minor trauma in pregnancy – can we limit cost without affecting outcomes?

The purpose of this study was to determine whether laboratory tests and extended fetal monitoring alter management and/or predict outcomes in women with viable pregnancies who endure minor trauma. A retrospective observational study of pregnant women who presented to Cooper University Hospital (CUH) between January 2010 to April 2019 for evaluation after sustaining minor trauma (defined as an Injury Severity Score less than 3). Standard protocol at CUH is to perform fetal and uterine contraction monitoring for up to 6 hours post-trauma, and collect a CBC, Type and Screen, Kleihauer-Betke, Fibrinogen, PT, and PTT. For this study, all fetal and uterine contraction monitoring was reviewed by a single investigator. Data was analyzed using Independent-t, Mann-Whitney U, Kruskal-Wallis, and x2 tests as indicated. Of the 260 women that met inclusion criteria for this study, 66 (25%) required admission and monitoring for greater than 6 hours. Laboratory values were not significantly different between women discharged after evaluation versus required prolonged observation (Table 1). The overall preterm delivery rate for this study (7.3%) and neonatal ICU admission rate (15%) was similar to the general population. There were no fetal demises; however, one placental abruption occurred. Pregnant women with less than 4 uterine contractions per hour in the first hour did not change their subsequent uterine contraction pattern for the remainder of monitoring. Routine laboratory tests drawn in pregnant women who sustained minor trauma did not determine admission for observation or discharge, nor did they predict adverse outcomes such as placental abruption, preterm birth, low birth weight, or NICU admission. Our study suggests that women with a reassuring fetal heart tracing and less than 4 uterine contractions in 1 hour of post trauma monitoring should not undergo routine laboratory tests or additional monitoring. Cost savings for the hospital are estimated to be more than $187,000 when using this approach for evaluation.

Consistency and timeliness of intrapartum care interventions as predictors of intrapartum stillbirth in public health facilities of Addis Ababa, Ethiopia: a case-control study.

Introductionapproximately one-third of the global stillbirth burden occurs during intrapartum period. Intrapartum stillbirths occurring in the health facilities imply that a foetus was alive on admission to labour and had greater chances of survival with optimum obstetric care. Active monitoring and follow-up by skilled birth attendants becomes critical to determine the progress of labour and to decide any emergency obstetrical care actions. Timely monitoring of labour progress indicators including fetal heart rate (FHR), uterine contraction maternal vital signs, vaginal examination (VE) are vital in reducing intrapartum stillbirth.Methodsa case-control study was conducted using primary data from chart review of medical records of women who experienced intrapartum stillbirth in 20 public health centres and 3 public hospitals of Addis Ababa between July 1st, 2010 to June 30th, 2015. Data were collected from charts of all cases of intrapartum stillbirths meeting the inclusion criteria and randomly selected charts of controls from each public health facility in 2: 1 control to case ratio.Resultsover 90% of both cases and controls received FHR monitoring care albeit the timing was substandard. More women in the live birth group than intrapartum stillbirth group received timely care related to uterine contraction (OR 2.42, 95% CI 1.77 - 3.30) and blood pressure monitoring (aOR 1.41, 95% CI 1.09 - 1.81). 1.2% and 0.3% of women in the intrapartum stillbirth and livebirth groups developed eclampsia respectively.Conclusionsubstandard timing and application of labour monitoring interventions including FHR, uterine contraction can predict intrapartum stillbirth in public health facilities.

Qualitative assessment of interpretability and observer agreement of three uterine monitoring techniques

ObjectiveThe aim of this research was to assess the quality and inter- and intra-observer agreement of tracings obtained by three different techniques for uterine contraction monitoring: the external tocodynamometer (TOCO), the intrauterine pressure catheter (IUPC) and a recently introduced method based on electrohysterography (EHG). Study designWe included 150 uterine activity registrations from a previous prospective observational study (W3 study), conducted at Máxima Medical Centre in Veldhoven, the Netherlands. Term singleton pregnant women were simultaneously monitored with TOCO, IUPC and EHG during labor. Six clinicians, blinded to the source (TOCO, IUPC, or EHG) and subject, evaluated all tracings that were subsequently presented in random order. They annotated contractions and assigned each tracing a score for interpretability of 2 (good), 1 (moderate) or 0 (poor). To evaluate inter-observer agreement, we calculated kappa values for the qualitative assessment, and intraclass correlation coefficients (ICC) for the number of contractions annotated by clinicians. Four clinicians repeated this procedure to evaluate intra-observer agreement. ResultsIUPC tracings received the highest quality rating, with a mean score of 1.95, followed by a mean score of 1.60 for EHG and 0.80 for TOCO (p < 0.05). Mean weighted kappa values were 0.63 for TOCO and 0.45 for EHG. The average number of contractions that was picked up by clinicians was 59.8 for the intrauterine pressure catheter, 49.8 for EHG and 26.4 for TOCO.The ICC of the intrauterine pressure catheter was significantly higher than the external methods, regarding both inter- and intra-observer agreement (0.98 and 0.99 respectively). ConclusionIUPC recordings scored best regarding quality, inter- and intra-observer agreement. However, due to safety issues, in many countries this technique is not used anymore. The quality of TOCO was rated as poor and many contractions were missed as compared to the gold standard. From a clinical interpretational point of view, EHG is favorable to TOCO. EHG recordings were assigned higher quality scores, but with less agreement between clinicians. An explanation could be that EHG is a relatively new technique, while IUPC and the TOCO are being used for decades. Building experience with EHG (training) is therefore recommended.

Automatic Contraction Detection Using Uterine Electromyography

Electrohysterography (EHG) is a promising technique for pregnancy monitoring and preterm risk evaluation. It allows for uterine contraction monitoring as early as the 20th gestational week, and it is a non-invasive technique based on recording the electric signal of the uterine muscle activity from electrodes located in the abdominal surface. In this work, EHG-based contraction detection methodologies are applied using signal envelope features. Automatic contraction detection is an important step for the development of unsupervised pregnancy monitoring systems based on EHG. The exploratory methodologies include wavelet energy, Teager energy, root mean square (RMS), squared RMS, and Hilbert envelope. In this work, two main features were evaluated: contraction detection and its related delineation accuracy. The squared RMS produced the best contraction (97.15 ± 4.66%) and delineation (89.43 ± 8.10%) accuracy and the lowest false positive rate (0.63%). Despite the wavelet energy method having a contraction accuracy (92.28%) below the first-rated method, its standard deviation was the second best (6.66%). The average false positive rate ranged between 0.63% and 4.74%—a remarkably low value.

Efficient EER-LEACH Protocol for Monitoring the Activities of Pregnant Women Using Wearable Body Sensor Network

In health care monitoring framework, it is important to always screen the patient's physiological parameters. For instance, pregnant lady parameters, like, blood pressure, uterine contraction heart rate of pregnant ladies and heart rate alongside the fetal development to detect their wellbeing condition. This paper introduces a monitoring framework that has the capacity to screen physiological changes from the pregnant ladies. In the proposed framework, controller node (CN) has connected on patient body to gather every one of the signs from the uterine contraction monitoring wearable body sensors and sends them to the base station. The appended sensors on patient's body frame a wireless body sensor network (WBSN) and they can detect the uterine constriction, heart rate, blood pressure etc. This framework can recognize the unusual conditions, issue an alert to the patient and send to the doctor. Likewise, the proposed framework comprises of a few relay nodes which are in charge of handing-off the information sent by the controller node (CN) and forward them to the base station. The principle effort of this framework is to diminish the vitality utilization to delay the system lifetime, accelerate and stretch out anticipated work is to expand the sensor execution. This framework is likewise created for multi-patient observing for hospital healthcare and contrasted with the current systems in view of coverage, energy utilization and speed.

Automated electrohysterographic detection of uterine contractions for monitoring of pregnancy: feasibility and prospects

BackgroundPreterm birth is a major public health problem in developed countries. In this context, we have conducted research into outpatient monitoring of uterine electrical activity in women at risk of preterm delivery. The objective of this preliminary study was to perform automated detection of uterine contractions (without human intervention or tocographic signal, TOCO) by processing the EHG recorded on the abdomen of pregnant women. The feasibility and accuracy of uterine contraction detection based on EHG processing were tested and compared to expert decision using external tocodynamometry (TOCO) .MethodsThe study protocol was approved by local Ethics Committees under numbers ID-RCB 2016-A00663-48 for France and VSN 02-0006-V2 for Iceland.Two populations of women were included (threatened preterm birth and labour) in order to test our system of recognition of the various types of uterine contractions.EHG signal acquisition was performed according to a standardized protocol to ensure optimal reproducibility of EHG recordings. A system of 18 Ag/AgCl surface electrodes was used by placing 16 recording electrodes between the woman’s pubis and umbilicus according to a 4 × 4 matrix. TOCO was recorded simultaneously with EHG recording.EHG signals were analysed in real-time by calculation of the nonlinear correlation coefficient H2. A curve representing the number of correlated pairs of signals according to the value of H2 calculated between bipolar signals was then plotted. High values of H2 indicated the presence of an event that may correspond to a contraction.Two tests were performed after detection of an event (fusion and elimination of certain events) in order to increase the contraction detection rate.ResultsThe EHG database contained 51 recordings from pregnant women, with a total of 501 contractions previously labelled by analysis of the corresponding tocographic recording. The percentage recognitions obtained by application of the method based on coefficient H2 was 100% with 782% of false alarms. Addition of fusion and elimination tests to the previously obtained detections allowed the false alarm rate to be divided by 8.5, while maintaining an excellent detection rate (96%).ConclusionThese preliminary results appear to be encouraging for monitoring of uterine contractions by algorithm-based automated detection to process the electrohysterographic signal (EHG). This compact recording system, based on the use of surface electrodes attached to the skin, appears to be particularly suitable for outpatient monitoring of uterine contractions, possibly at home, allowing telemonitoring of pregnancies. One of the advantages of EHG processing is that useful information concerning contraction efficiency can be extracted from this signal, which is not possible with the TOCO signal.

Focus on cardiotocography: Intrapartum monitoring of uterine contractions

When undertaking training on electronic fetal monitoring, much is discussed about the fetal heart rate and less on the uterine contractions. This is also reflected when discussing the history of both fetal heart rate monitoring and uterine contraction monitoring.Adequately monitoring the uterine contractions is an essential part of cardiotocography. It allows for an assessment of the fetal heart rate in relation to the uterine contractions, especially when there is a non-reassuring or an abnormal trace. When oxytocin is used in induced or augmented labours, it is imperative to ensure that there is no evidence of uterine hyperstimulation and that sufficient resting phases occur between contractions. However, assessing contractions adequately can be challenging in practice, especially in cases of obese parturients.This article explores the methods used to assess uterine contractions, using clinical skills in conjunction with external tocodynamometry and electrohysterography, as well as exploring some of the background to monitoring uterine contractions.

DEVELOPMENT OF UTERINE CONTRACTION MONITORING SYSTEM FOR RESOURCE-LIMITED SETTINGS

A need assessment exercise at various resource-limited hospitals in Ghana revealed that a conventional method of monitoring uterine contractions is employed. This method is time consuming and ineffective with a likelihood of misrepresenting data on uterine contractions. There is therefore a need for a system that can potentially overcome the identified challenges. In this paper, the authors present the proof of concept for development of an automated uterine contraction monitoring system designed for use in resource-limited settings. Following the engineering design process, data were gathered to draft product specifications. Various concepts were evaluated and a mathematical model of chosen concept was built and simulated. A functional prototype was constructed to test the system’s ability to measure the frequency and average duration of muscle contractions over a specified interval. The results indicate the capability of the chosen concept to meet design specifications. The design can also be enhanced to provide the intensity of contractions.

Group B Streptococcus circumvents neutrophils and neutrophil extracellular traps during amniotic cavity invasion and preterm labor.

Preterm birth is a leading cause of neonatal morbidity and mortality. Although microbial invasion of the amniotic cavity (MIAC) is associated with the majority of early preterm births, the temporal events that occur during MIAC and preterm labor are not known. Group B Streptococci (GBS) are β-hemolytic, gram-positive bacteria, which commonly colonize the vagina but have been recovered from the amniotic fluid in preterm birth cases. To understand temporal events that occur during MIAC, we utilized a unique chronically catheterized nonhuman primate model that closely emulates human pregnancy. This model allows monitoring of uterine contractions, timing of MIAC and immune responses during pregnancy-associated infections. Here, we show that adverse outcomes such as preterm labor, MIAC, and fetal sepsis were observed more frequently during infection with hemolytic GBS when compared to nonhemolytic GBS. Although MIAC was associated with systematic progression in chorioamnionitis beginning with chorionic vasculitis and progressing to neutrophilic infiltration, the ability of the GBS hemolytic pigment toxin to induce neutrophil cell death and subvert killing by neutrophil extracellular traps (NETs) in placental membranes in vivo facilitated MIAC and fetal injury. Furthermore, compared to maternal neutrophils, fetal neutrophils exhibit decreased neutrophil elastase activity and impaired phagocytic functions to GBS. Collectively, our studies demonstrate how a unique bacterial hemolytic lipid toxin enables GBS to circumvent neutrophils and NETs in placental membranes to induce fetal injury and preterm labor.

Vaginal electrohysterography: the design and preliminary evaluation of a novel device for uterine contraction monitoring in an ovine model*

Objective: Tocodynamometry is the most common method of labor evaluation but most clinicians would agree it has limited utility before 26 weeks of gestation. The obesity epidemic has further reduced our ability to accurately detect uterine contractions using the tocodynamometer at any gestational age. We sought to design and test a novel contraction monitor that bypasses the maternal abdomen. Methods: An optimized version of an intravaginal electrohysterographic ring device was tested in an ovine model. The device and its methodology as well as the tocodynamometer were validated against the current gold standard uterine activity monitor, the intrauterine pressure catheter in six sheep at varying gestational ages. Results: Both the intravaginal ring device and the tocodynamometer correlated well with IUPC, r = 0.69 and 0.73, respectively (p < 0.001). The number of contractions detected by each monitor remained similar even after accounting for confounders. Conclusions: These results suggest that uterine activity can be monitored from the vaginal interface in an ovine model and offers an alternative clinical tool for the detection of contractions in situations, in which tocodynamometry would be ineffective or intrauterine monitoring inappropriate.

Combining latent class analysis labeling with multiclass approach for fetal heart rate categorization

The most common approach to assess fetal well-being during delivery is monitoring of fetal heart rate and uterine contractions—the cardiotocogram (CTG). Nevertheless, 40 years since the introduction of CTG to clinical practice, its evaluation is still challenging with high inter- and intra-observer variability. Therefore the development of more objective methods has become an issue of major importance in the field. Unlike the usually proposed approaches to assign classes for classification methods that rely either on biochemical parameters (e.g. pH value) or a simple aggregation of expert judgment, this work investigates the use of an alternative labeling system using latent class analysis (LCA) along with an ordinal classification scheme. The study is performed on a well-documented open-access database, where nine expert obstetricians provided CTG annotations. The LCA is proposed here to produce more objective class labels while the ordinal classification aims to explore the natural ordering, and representation of increased severity, for obtaining the final results. The results are promising suggesting that more effort should be put into this proposed approach.