Fetal Heart Rate Parameters Research Articles

Fetal cardiovascular changes during open and fetoscopic in-utero spina bifida closure.

Fetoscopic closure of spina bifida using heated and humidified carbon dioxide gas (hhCO2) has been associated with lower maternal morbidity compared with open closure. Fetal cardiovascular changes during these surgical interventions are poorly defined. Our objective was to compare fetal bradycardia (defined as fetal heart rate (FHR) < 110 bpm for 10 min) and changes in umbilical artery (UA) Doppler parameters during open vs fetoscopic closure. This was a prospective cohort study of 22 open and 46 fetoscopic consecutive in-utero closures conducted between 2019 and 2023. Both cohorts had similar preoperative counseling and clinical management. FHR and UA Doppler velocimetry were obtained systematically during preoperative assessment, every 5 min during the intraoperative period, and during the postoperative assessment. FHR, UA pulsatility index (PI) and UA end-diastolic flow (EDF) were segmented into hourly periods during surgery, and the lowest values were averaged for analysis. Umbilical vein maximum velocity was measured in the fetoscopic cohort. At each timepoint at which FHR was recorded, maternal heart rate and systolic and diastolic blood pressure were measured. Fetal bradycardia occurred in 4/22 (18.2%) cases of open closure and 21/46 (45.7%) cases of fetoscopic closure (P = 0.03). FHR decreased gradually in both cohorts after administration of general anesthesia and decreased further during surgery. FHR was significantly lower during hour 2 of surgery in the fetoscopic-repair cohort compared with the open-repair cohort. The change in FHR from baseline in the final stage of fetal surgery was significantly more pronounced in the fetoscopic-repair cohort compared with the open-repair cohort (mean, -32.4 (95% CI, -35.7 to -29.1) bpm vs -23.5 (95% CI, -28.1 to -18.8) bpm; P = 0.002). Abnormal UA-EDF (defined as absent or reversed EDF) occurred in 3/22 (13.6%) cases in the open-repair cohort and 23/46 (50.0%) cases in the fetoscopic-repair cohort (P = 0.004). There were no differences in UA-EDF or UA-PI between closure techniques at the individual stages of assessment. We observed a decrease in FHR and abnormalities in UA Doppler parameters during both open and fetoscopic spina bifida closure. Fetal bradycardia was more prominent during fetoscopic closure following hhCO2 insufflation, but FHR recovered after cessation of hhCO2. Changes in FHR and UA Doppler parameters during in-utero spina bifida closure were transient, no cases required emergency delivery and no fetoscopic closure was converted to open closure. These observations should inform algorithms for the perioperative management of fetal bradycardia associated with in-utero spina bifida closure. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

The Value of Non-invasive Electrocardiography in Assessing Fetal Status at Term Delivery.

The electrocardiograph (ECG) is efficient method for the accurate assessment of fetal heart rate. The barriers for accurate assessment are maternal heart rate, uterine contractions and abdominal muscles. Although previous monitoring methods have struggled to overcome these barriers, recent advances have led to a greater degree of success for listening and recording pulse-by-pulse fetal heart rate. A prospective cohort study evaluating the use, reliability and safety of non-invasive electrocardiography, in conjunction with Fetal Heart Rate parameters such as, Short Term Variability (STV) together with umbilical cord PH and Apgar score, during the active phase of childbirth. A total of 41 women with single, normal, full-term pregnancies had systematic obstetric monitoring with Monica AN24. 20 had only monitoring and 21 also had and arterial blood flow measurements. pH was measured and correlated with neonatal Apgar score at 1 and 5 min. The study also included a questionnaire about the safety and usability of obstetric monitoring. Statistical analysis was done using IBM SPSS v. 26.0. Mean age was 28.8 years, (SD ± 6.153). Electrocardiogram recordings (ECG) were classified as normal (71%) and suspicious (29%). Baseline between ECGs was different (p = 0.025) similarly for Short term variability (STV) (p <0.0001). BMI did not differentiate SVT rates. Only high acceleration (p <0.029) and small slowdowns had a statistically significant difference between normal and suspected cardiographs (p <0.029). APGAR score did not differ, whereas the umbilical cord pH was different in normal ECGs compared to the suspect (p = 0.012) and STV was also differentiated. A usability and safety survey was conducted after recording with MONIKA AN24, and the response to whether they would accept recording with the device again, was positive for 96% of the 30 responders. The present study shows that the use of electrocardiography in obstetrics allows to draw conclusions about the fetal hematopoiesis and oxygenation status. This method could be clinically applied and be an important tool for further screening in embryos that may be hypoxic and to decide whether to continue with a vaginal or cesarean delivery, thereby achieving the goal of reducing perinatal morbidity and mortality.

A study on risk factors and outcome in prelabour rupture of membrane

Background and Objectives: During the last three decades it has taken a new dimension because of identification of clinical risk factors and improved fetomaternal outcome due to better management. The present study aimed to assess the maternal and fetal outcome in patients with prelabour rupture of membrane. Methods: The present prospective cross-sectional study was conducted among the patients presenting with spontaneous rupture of membrane, admitted in Department of OBG of Al-Ameen Medical College Medical College, Athani road, Vijayapura. Informed consent was taken from all enrolled patients after detailed counselling. The contents of the consent were read out to the patients in his language. Detailed history taking including age, parity, weight gain, inter pregnancy interval. History emphasized on exact time of rupture of membrane and duration the amount of leak. Detailed examination like blood pressure, height, temperature was noted. In obstetric history uterine height, fetal presentation, fetal heart rate, estimated weight and other parameters of maternal and fetalwell-being was noted. A sterile speculum examination was conducted and presence of liquor amini was noted. The maternal and fetal outcome were monitored and recorded in the Performa. All the data were entered in excel sheet and the analysis was performed using SPSS V.21.0 operating on windows 10. Results: Present study total of 100 patients fulfilling inclusion criteria are included in present study after obtaining the informed consent. The mean age of the patients was found to be 24.92. The maternal complications seen among patients were with 34% puerperal fever, followed with 10% with wound infections and 3% with UTI. Among the fetal complications, the study documented majority with presence of respiratory distress syndrome in 17% of the newborn, followed with 4% meconium aspiration, 3% with conjunctivitis and 1% with sepsis and still birth. Conclusion: The present study documented the major etiological factors for PROM among study participants was following the coitus, followed with history of previous pregnancy leaking. The study also documented the common mode of delivery was lower segment caesarean section with cause of failure to progress among them. The maternal complication documented was majority with puerperal fever and wound infection. The newborn complication documented was majority with respiratory distress syndrome followed with meconium aspiration.

Heart rate markers for prediction of fetal acidosis in an experimental study on fetal sheep

To overcome the difficulties in interpreting fetal heart rate (FHR), several tools based on the autonomic nervous system and heart rate variability (HRV) have been developed. The objective of this study was to use FHR and HRV parameters for the prediction of fetal hypoxia. It was an experimental study in the instrumented fetal sheep. Repeated umbilical cord occlusions were performed to achieve severe acidosis. Hemodynamic parameters, ECG, and blood gases were analyzed. The variables used were heart rate baseline, HRV analysis (RMSSD, SDNN, LF, HF, HFnu, Fetal Stress Index (FSI), …), and morphological analysis of decelerations. The gold standard used to classify hypoxia was the fetal arterial pH (pH < 7.10). Different multivariable statistical methods (logistic regression and decision trees) were applied for the detection of acidosis. 21 lambs were instrumented. A total of 130 pairs of FHR/fetal pH analysis were obtained of which 29 in the acidosis group and 101 in the non-acidosis group. After logistic regression model with bootstrap resampling and stepwise backward selection, only one variable was selected, FSI. The AUC of FSI alone in this model was 0.81 with a sensitivity of 0.66, specificity of 0.88, PPV of 0.61, and NPV of 0.90 considering a threshold of 68. Decision trees with CHAID and CART algorithms showed a sensitivity of 0.48 and 0.59, respectively, and a specificity of 0.94 for both. All employed methods identified HRV variables as the most predictive of acidosis. The primary variables selected automatically were those from the HRV. Supporting the use of FHRV measures for the screening of fetal acidosis during labour is interesting.

Music Modulates Autonomic Nervous System Activity in Human Fetuses.

ContextFetal Autonomic Nervous sysTem Evaluation (FANTE) is a non-invasive tool that evaluates the autonomic nervous system activity in a fetus. Autonomic nervous system maturation and development during prenatal life are pivotal for the survival and neuropsychiatric development of the baby.ObjectiveAim of the study is to evaluate the effect of music stimulation on fetal heart rate and specific parameters linked to ANS activity, in particular fetal heart rate variability.MethodsThirty-two women between the 32nd and 38th week with a singleton uncomplicated pregnancy were recruited. All FANTE data collections were acquired using a 10-derivation electrocardiograph placed on the maternal abdomen. In each session (5 min basal, 10 min with music stimulus, and 5 min post-stimulus), FANTE was registered. The music stimulus was “Clair de lune” Debussy, played through headphones on the mother’s abdomen (CTR: 31927).ResultsMusic does not change the mean value of fetal heart rate. However, indices of total fetal heart rate variability statistically increase (RRsd p = 0.037, ANNsd p = 0.039, SD2 p = 0.019) during music stimulation in comparison to the basal phase. Heart rate variability increase depends mainly on the activation of parasympathetic branches (CVI p = 0.013), meanwhile, no significant changes from basal to stimulation phase were observed for indices of sympathetic activity. All the parameters of heart rate variability and parasympathetic activity remained activated in the post-stimulus phase compared to the stimulus phase. In the post-stimulus phase, sympathetic activity resulted in a significant reduction (LFn p = 0.037).ConclusionMusic can influence the basal activity of the fetal autonomic nervous system, enhancing heart rate variability, without changing fetal heart rate mean value. Music is enabled to induce a relaxation state in a near-to-term fetus, mediated by parasympathetic activation and by a parallel sympathetic inhibition.

Investigating association relationship between fetal heart rate parameters from cardiotocography employing multi-objective evolutionary algorithms

Investigating association relationship between fetal heart rate parameters from cardiotocography employing multi-objective evolutionary algorithms

Analyses of Fetal Heart Rate Parameters and Dynamics Based on Fetal Movement and Health at the Time of Delivery

Analyses of Fetal Heart Rate Parameters and Dynamics Based on Fetal Movement and Health at the Time of Delivery

FETAL TYPE CLASSIFICATION BASED ON FETAL ELECTROCARDIOGRAPH IN NON-STRESS TESTS

Electronic fetal heart rate (FHR) monitoring is a technical means to evaluate the state of the fetus in the uterus by monitoring FHR. The main purpose is to detect intrauterine hypoxia and take corresponding medical measures timely. Because the fetus sleeps quietly for up to 1 hour sometimes, ultrasound Doppler is not easy to continuously detect for a long time. The electronic fetal monitor obtains the fetal heart rate, which not only improves the accuracy and comfort, but also the convenient implementation of long-term monitoring. It is beneficial to reduce perinatal fetal morbidity and mortality. This study used maternal–fetal Holter monitor which is based on the technology of fetal electrocardiograph (FECG) to collect the FHR, and then design algorithm to extract the baseline FHR, acceleration, variation, sleep-wake cycle and nonlinear parameters. There were significant differences in the 22 parameters between the normal and the suspicious group. Using the 22 characteristic parameters, the support vector machine was used to classify the normal and the suspected group of fetuses. 80% of the data was used to train a classification model. The remaining 20% of the data was used as a test set and its accuracy reached 93.75%.

Fetal heart rate monitoring during fetoscopic repair of open spinal neural tube defects: a single-centre observational cohort study

BackgroundDuring fetal surgery, the haemodynamic stability of the fetus depends on the haemodynamic stability of the mother. The primary objective of this study was to assess changes in fetal heart rate (FHR) throughout the different stages of surgery. The secondary objective was to assess potential changes in maternal physiological parameters and their association with FHR. MethodsThis was a single-center observational cohort study conducted between 2015 and 2019 in 26 women undergoing intra-uterine fetoscopic repair of open spina bifida. The primary outcome was FHR. Maternal physiologic parameters were measured at the beginning, during and after surgery. The linear mixed-effects model fitted by maximum likelihood was used to assess changes in each variable at specific times throughout the surgery, and the repeated measures correlation coefficient was used to study the association between FHR and maternal physiological parameters. ResultsOne (3.8%) case of fetal bradycardia (FHR <110 beats per minute) required the administration of intramuscular atropine. No other significant FHR changes were observed during surgery. Maternal oesophageal temperature (P <0.001), lactate levels (P=0.002), and mean arterial pressure (P=0.016) changed significantly during surgery, although none of these changes was clinically relevant. The FHR showed a significant association with maternal carbon dioxide tension (r=0.285, 95% CI 0.001 to 0.526) and maternal heart rate (r=0.302, 95% CI 0.025 to 0.535). ConclusionThe FHR remained stable during intra-uterine fetoscopic repair of open spina bifida. Maternal carbon dioxide tension and heart rate may have a mild influence on FHR.

Effect of Dexamethasone on Antepartum Cardiotocography

Objective: The purpose of this study was to evaluate the effect of dexamethasone on fetal heart rate parameters using the standard dose regimen. Study Design: A prospective cohort study conducted in the Maternity Department, Suez Canal University hospitals. Sixty- eight pregnant women with gestational age between 28 and 34 weeks were recruited. Patients received 4 doses of dexamethasone 6 mg every 12 hours for threatened preterm delivery due to preterm premature rupture of membranes, placenta previa or history of preterm labor. Computerized cardiotocography was recorded for 60 minutes on day 0 (before dexamethasone administration), day 2 and day 4 after administration. Cardiotocography monitoring was performed between 11 am and 1 pm to avoid diurnal rhythm of fetal heart rate. Outcome measure included changes in fetal heart rate accelerations, variability and fetal movements following dexamethasone injection. Results: Sixty-eight patients were enrolled in the study. Fetal heart rate accelerations (P=0.0001), short-term variation (P=0.01), episodes of high variation (P=0.003) and fetal movements (P=0.0001) were significantly reduced on day 2 after dexamethasone. No significant changes were found on baseline fetal heart rate (P=0.18), long-term variation (P=0.1) and number of decelerations (P=0.1). All parameters returned to baseline values on Day 4 after administration. Conclusion: Dexamethasone induces transient suppression of fetal heart rate parameters on day 2 after administration that mimics fetal compromise. Awareness of this phenomenon is important to avoid iatrogenic delivery of preterm fetuses.

Prenatal maternal psychological distress and fetal developmental trajectories: associations with infant temperament.

Associations between prenatal maternal psychological distress and offspring developmental outcomes are well documented, yet relatively little research has examined links between maternal distress and development in utero, prior to postpartum influences. Fetal heart rate (FHR) parameters are established indices of central and autonomic nervous system maturation and function which demonstrate continuity with postnatal outcomes. This prospective, longitudinal study of 149 maternal-fetal pairs evaluated associations between prenatal maternal distress, FHR parameters, and dimensions of infant temperament. Women reported their symptoms of psychological distress at five prenatal visits, and FHR monitoring was conducted at the last three visits. Maternal report of infant temperament was collected at 3 and 6 months of age. Exposure to elevated prenatal maternal psychological distress was associated with higher late-gestation resting mean FHR (FHRM) among female but not male fetuses. Higher late-gestation FHRM was associated with lower infant orienting/regulation and with higher infant negative affectivity, and these associations did not differ by infant sex. A path analysis identified higher FHRM as one pathway by which elevated prenatal maternal distress was associated with lower orienting/regulation among female infants. Findings suggest that, for females, elevated maternal distress alters fetal development, with implications for postnatal function. Results also support the notion that, for both sexes, individual differences in regulation emerge prenatally and are maintained into infancy. Collectively, these findings underscore the utility of direct assessment of development in utero when examining if prenatal experiences are carried forward into postnatal life.

Is short-term-variation of fetal-heart-rate a better predictor of fetal acidaemia in labour? A feasibility study.

Continuous intrapartum fetal monitoring is challenging and its clinical benefits are debated. The project evaluated whether short-term-variation (STV) and other computerised fetal heart rate (FHR) parameters (baseline FHR, long-term-variation, accelerations and decelerations) predicted acidaemia at birth. The aims of the study were to assess the changes in FHR pattern during labour and determine the feasibility of undertaking a definitive trial by reporting the practicalities of using the monitoring device, participant recruitment, data collection and staff training. 200 high-risk women carrying a term singleton, non-anomalous fetus, requiring continuous FHR monitoring in labour were consented to participate from the Jessop Wing maternity unit, Sheffield, UK. The trans-abdominal fetal ECG monitor was placed as per clinical protocol. During the monitoring session, clinicians were blinded to the computerised FHR parameters. We analysed the last hour of the FHR and its ability to predict umbilical arterial blood pH <7.20 using receiver operator characteristics (ROC) curves. Of 200 women, 137 cases were excluded as either the monitor did not work from the onset of labour (n = 30), clinical staff did not return or used the monitor on another patient (n = 37), umbilical cord blood not obtained (n = 25), FHR data not recorded within an hour of birth (n = 34) and other reasons (n = 11). In 63 cases included in the final analysis, the computer-derived FHR parameters did not show significant correlation with umbilical artery cord pH <7.20. Labour was associated with a significant increase in short and long term variation of FHR and number of deceleration (P<0.001). However, baseline FHR decreased significantly before delivery (P<0.001). The project encountered a number of challenges, with learning points crucial to informing the design of a large study to evaluate the potential place of intrapartum computerised FHR parameters, using abdominal fetal ECG monitor before its clinical utility and more widespread adoption can be ascertained.

0853 Fetal Heart Rate Variability Increases During Maternal Sleep Apnea Events

Abstract Introduction While studies have established that SDB during pregnancy increases the risk of adverse maternal outcomes, fetal effects are less well studied. Evidence suggests that fetal heart rate decelerations, an indicator of fetal distress, may be elicited by SDB. We examined the relationship between maternal SDB events and fetal heart rate (FHR) and fetal heart rate variability (FHRV). Methods Obese (BMI≥30kg/m2) non-smoking women carrying singleton fetuses underwent overnight polysomnography (34-37 weeks gestational age), with simultaneous fetal heart rate monitoring. Standard methods were used to score sleep, SDB events (apneas/hypopneas) and to analyze fetal heart rate parameters. Using linear mixed effect models, we examined changes in mean FHR and FHR variability (expressed by FHR SD) between the 10-second period immediately before individual SDB events, during events to the end of the associated oxygen desaturation period, and the 10-second period immediately following the SDB event. Results Valid PSG and FHR data were obtained from 85 third trimester maternal-fetal dyads. Across all participants, there were 2779 maternal SDB events (apneas or hypopneas). Mean AHI for individual subjects was 9.04 (SD 13.75). 39 women had OSA (AHI≥5), which was mostly mild. Mean FHR did not change significantly during and after episodes of SDB episodes compared to pre-event FHR, and did not change afterwards compared to during events, in unadjusted or adjusted (sleep stage, apnea type, degree of desaturation, age) analyses. In unadjusted analyses, FHRV significantly increased during SDB episodes compared to pre-SDB FHRV. After SDB events, FHRV was significantly lower than during SDB events. In fully adjusted models, these findings remained highly significant. FHRV was not significantly different after SDB events compared to pre-SDB event FHRV in unadjusted or adjusted models. Conclusion We observed consistent changes in FHR variability during and after maternal SDB events. Mean FHRV significantly increased during maternal SDB episodes compared to baseline FHRV, and decreased after SDB episodes. In contrast, mean FHR did not change significantly before, during and after SDB episodes. These data demonstrate that the fetus reacts to maternal SDB events, and raise questions about persistent effects of maternal SDB on the developing fetus. Support NIH HD079411

249: Deceleration area-time ratio as predictor of acidemia in fetuses with early onset growth restriction

There is little existing literature to guide the interpretation of fetal heart rate tracings in growth restricted fetuses with abnormal Doppler studies remote from term. This study sought to determine fetal heart rate parameters associated with fetal acidemia. Data was collected prospectively on 14 pregnancies diagnosed with early-onset intrauterine growth restriction with abnormal umbilical artery Dopplers. All women included in this analysis delivered at less than 32 weeks gestation and had an umbilical artery pH obtained at time of delivery. An investigator blinded to the umbilical cord pH analyzed the last 60 minutes of fetal heart rate tracing prior to delivery and recorded baseline, variability, presence of accelerations, number of decelerations, maximum depth of deceleration, total time spent in deceleration, and total deceleration area (TDA). TDA was defined as area below the fetal baseline in units of 10 beats per 10 seconds. From these data, the ratio of TDA over total deceleration time (TDA/time) was calculated (see Figure 1). Receiver operating characteristic (ROC) curves were used to analyze the ability of each of these parameters to predict umbilical cord pH less than 7.00 and less than 7.10. A p-value < .05 was considered significant. Of the 14 women, 2 had umbilical cord pH values less than 7.00 and 5 with pH less than 7.10. The area under the curve for TDA-time ratio was 1.00 for pH less than 7.00 and .80 for pH less than 7.10. The areas under the curve showed poor predictive value of maximum depth of decelerations, number of decelerations, time spent in deceleration, and TDA (Table 1). A TDA/time cut-off of .15 had a 100% specificity and sensitivity for predicting pH less than 7.0 and a 100% specificity and 40% sensitivity for predicting pH less than 7.10. In this cohort, the TDA/time ratio was the strongest predictor of an abnormal umbilical artery pH, suggesting long, shallow decelerations are of greatest concern in these patients. This represents a novel technique for quantifying these decelerations.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Use of automated fetal heart rate analysis to identify risk factors for umbilical cord acidosis at birth

ObjectiveTo identify clinical parameters and intrapartum fetal heart rate parameters associated with a risk of umbilical cord acidosis at birth, using an automated analysis method based on empirical mode decomposition. MethodsOur single-center study included 381 cases (arterial cord blood pH at birth pHa ≤7.15) and 1860 controls (pHa ≥7.25) extracted from a database comprising 8,383 full datasets for over-18 mothers after vaginal or caesarean non-twin, non-breech deliveries at term (>37 weeks of amenorrhea). The analysis of a 120-min period of the FHR recording (before maternal pushing or the decision to perform a caesarean section during labor) led to the extraction of morphological, frequency-related, and long- and short-term heart rate variability variables. After univariate analyses, sparse partial least square selection and logistic regression were applied. ResultsSeveral clinical factors were predictive of fetal acidosis in a multivariate analysis: nulliparity (odds ratio (OR) 95% confidence interval (CI)]: 1.769 [1.362–2.300]), a male fetus (1.408 [1.097–1.811]), and the term of the pregnancy (1.333 [1.189–1.497]). The risk of acidosis increased with the time interval between the end of the FHR recording and the delivery (OR [95%CI] for a 1-min increment: 1.022 [1.012–1.031]). The risk factors related to the FHR signal were mainly the difference between the mean baseline and the mean FHR (OR [95%CI]: 1.292 [1.174–1.424]), the baseline range (1.027 [1.014–1.040]), fetal bradycardia (1.038 [1.003–1.075]) and the late deceleration area (1.002 [1.000–1.005]). The area under the curve for the multivariate model was 0.79 [0.76; 0.81]. ConclusionIn addition to clinical predictors, the automated FHR analysis highlighted other significant predictors, such as the baseline range, the instability of the FHR signal and the late deceleration area. This study further extends the routine application of automated FHR analysis during labor and, ultimately, contributes to the development of predictive scores for fetal acidosis.

An antenatal marker of neurodevelopmental outcomes in infants with congenital heart disease

ObjectivePrenatal exposures are known to alter fetal neurodevelopment and autonomic control. We aimed to explore the correlation between fetal autonomic activity, measured by fetal heart rate variability, and 18-month developmental outcome in subjects with congenital heart disease.Study DesignFrom 2010–2013, 5 fetuses with hypoplastic left heart syndrome, 9 with transposition of the great arteries, and 9 with tetralogy of Fallot were included in this prospective cohort study. A maternal abdominal fetal electrocardiogram monitor recorded fetal heart rate at 34–38 weeks gestational age. We assessed associations between fetal heart rate parameters including interquartile range and standard deviation of the fetal RR intervals and 18-month Bayley Scales of Infant Development III scores using Pearson’s correlation coefficient. Multivariable regression modeling identified predictors of neurodevelopmental scores.ResultsFetal heart rate variability parameters at 34–38 weeks gestational age correlated with 18-month Cognition (r=0.47, p=0.03) and Motor scores (r=0.66, p=0.001). The interquartile range of the fetal RR intervals predicted Cognition (β=0.462, p=0.028, R2=0.282) and Motor (β=0.637, p<0.001, R2=0.542) scores.ConclusionsIn fetuses with congenital heart disease, low heart rate variability at 34–38 weeks gestational age predicts diminished 18-month cognitive and motor performance. Prenatal autonomic activity may serve as a marker of early childhood development in these high-risk patients.

Assessing effects of BL67 points stimulation on fetal heart rate parameters and fetal movements during nonstress test.

CONTEXT:One of the main goals of antenatal testing is to identify fetuses at the risk of neurologic injury or death so that these adverse outcomes can be prevented. We want to assess the effects of BL67 points’ stimulation on fetal heart rate parameters and fetal movements during nonstress test (NST). We did a quasi-experimental design in Shahid Beheshti Hospital in Isfahan in 2011.AIMS:This study aims to assessment of the effects of BL67 points’ stimulation on fetal heart rate parameters and fetal movements.SETTINGS AND DESIGN:We did a randomized controlled clinical trial in Shahid Beheshti Hospital in Isfahan in 2011.SUBJECTS AND METHODS:This study is a quasi-experimental design that was conducted in one group and the two steps (before-after study). Participants were pregnant women (primigravida) who were 35–18 years that refer to Shahid Beheshti Hospital in Isfahan in 2011 to receive routine prenatal care. The 32 pregnant women were selected for acupressure during the second NST.STATISTICAL ANALYSIS USED:The statistical processing was performed by descriptive, paired t-test through SPSS version 20.RESULTS:There was no significant difference in mean number of accelerations in fetal heart rate and mean number of fetal movement before and after intervention; however, there was a significant difference in mean time to the second acceleration before and after the intervention (P = 0.04).CONCLUSIONS:No difference between parameters of the fetal heart rate before and after stimulation and lack of uterine response by this method is a significant advantage and is probably why stimulating this point could not create a risk to the fetuses.

Circadian changes and sex-related differences in fetal heart rate parameters.

BackgroundPrevious researchers have studied circadian changes in the fetal heart rate (FHR) on small sample sizes and in a strictly controlled environment. This study was undertaken to investigate these changes during the late second and third trimesters, using a portable fetal electrocardiogram recording device (Monica AN24) in pregnant women in home and hospital environments with unrestricted mobility.MethodsThis was a prospective cohort study of 54 pregnant women with uncomplicated singleton pregnancies between 25 and 40 weeks gestation. FHR recordings were made up to 16 h at home or in the hospital setting in the United Kingdom. FHR data over 90 min periods were averaged and the day (7:00 am–11:00 pm) and night (11:00 pm–7:00 am) data from the same individual were compared. Data were examined for evidence of sex-related differences.ResultsDuring the night, there was a significant reduction in basal heart rate (bFHR) and a significant increase in short term variation (STV) and long term variation (LTV) (P < 0.05). Basal FHR decreased (P < 0.002), whereas LTV increased (P = 0.014) with advancing gestation. Male fetuses showed greater day: night variation than females regardless of gestation (P = 0.014). There was a higher bFHR in fetuses monitored during the day in hospital (P = 0.04).ConclusionThis study demonstrates that there are sex-, environment and time-related differences in the FHR parameters measured. These differences may need to be considered taken when interpreting FHR data.

Fetal gastroschisis: antepartum fetal heart rate analysis by computerized cardiotocography

Objectives: To describe the antenatal fetal heart rate (FHR) parameters analyzed by computerizedcardiotocography (cCTG) in fetuses with gastroschisis and compare the FHR parameters with ultrasound gastrointestinal markers.Methods: A retrospective analysis of antepartum cCTG records were conducted in 87 pregnant cases with fetal gastroschisis between 28and 36 weeks (plus 6 days). A comparative analysis of the median distribution of the following FHR parameters was performed: basal FHR, short-term variation (STV), FHR accelerations and decelerations, episodes of high and low variations, and variations in low and high episodes. FHR parameters and ultrasound gastrointestinal markers were also compared.Results: The majority of FHR parameters did not present significant changes throughout gestation. An increased number of records with episodes of low variation (p = 0.019) and an increased number of accelerations >15 bpm (p = 0.001) were the only observed changes throughout gestation. Stomach herniation was significantly associated with a lower STV (p = 0.018) and a higher frequency of records with low episodes (p = 0.049).Conclusions: The cCTG analysis indicated that the FHR parameters in fetuses with gastroschisis presented different patterns from those observed in normal fetuses. Stomach herniation was associated with altered FHR patterns.

Nonlinear analysis of fetal heart rate dynamics in fetuses compromised by asymptomatic partial placental abruption

IntroductionWe analyzed fetal heart rate (FHR) parameters, dynamics, and outcomes in pregnancies with asymptomatic partial placental abruption (PPA) compared with those in normal pregnancies. MethodsWe examined nonstress test (NST) data acquired from 2003 to 2012 at our institution. Normal pregnancies (N = 170) and PPA cases (N = 17) were matched for gestational age, fetal sex, and mean FHR. NSTs were performed at 33–42 weeks of gestation. FHR parameters obtained from the NST and perinatal outcomes were analyzed using linear methods. Nonlinear indices, including approximate entropy (ApEn), sample entropy (SampEn), short-term and long-term scaling exponents (α1 and α2), and correlation dimension (CD), were used to interpret FHR dynamics and system complexity. The area under a receiver operating characteristic curve (AUC) was used to evaluate the nonlinear indices. ResultsThere were no significant differences in general characteristics and FHR parameters between the PPA and control groups. However, gestational age at delivery, birth weight, 5-min Apgar scores, ApEn, SampEn, and CD were significantly lower in the PPA group than in the control group (P < 0.05). The long-term scaling exponent (α2) and crossover index (α2/α1) of the PPA fetuses were significantly higher than those of the controls (P < 0.01). A multiple regression model showed better performance in predicting PPA (AUC, 0.92; sensitivity 82.35%; specificity, 94.12%). DiscussionNonlinear dynamic indices of FHR in asymptomatic PPA were qualitatively different from those in normal pregnancies, whereas the conventional FHR parameters were not significantly different.