Effects of maternal breathing rate, psychiatric status, and cortisol on fetal heart rate

Women's experiences during pregnancy are predictive of variation in neurobehavioral profiles in their children. Few studies have assessed these relationships during the prenatal period. In 113 women in the 36^th –38^th gestational week (mean age 26.3 ± 5.4 years), electrocardiogram, blood pressure, respiration, salivary cortisol, and fetal heart rate (HR) were measured during baseline, a psychological challenge (Stroop color–word matching task), and a standardized paced breathing protocol. Subjects underwent the Structured Clinical Interview for DSM‐IV prior to testing and were grouped as: depressed, co–morbid for depression and anxiety, anxiety disorder only, and control. There was a significant main effect of maternal diagnostic group on fetal HR only during the Stroop task: fetuses of women in the co–morbid group had a greater HR increase compared to controls (p < .05). Overall, fetuses showed robust increases in HR during paced breathing (p < .0001), and there was no significant difference by maternal diagnosis. For both tasks, changes in fetal HR were independent of women's concurrent cardiorespiratory activity. Finally, although cortisol was higher in the co‐morbid group (p < .05), across all participants, there was a trend for maternal baseline cortisol to be positively associated with average fetal HR (p = .06). These findings indicate that variation in fetal HR reactivity—an index of emerging regulatory capacities—is likely influenced by multiple acute and chronic factors associated with women's psychobiology. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 53:221–233, 2011.     

产前产时胎心监护对胎儿窘迫的诊断价值

目的探讨产前、产时胎心监护异常曲线与胎儿窘迫的之间关系。方法对住院分娩2320例孕妇产前、产时电子胎心监护图形进行分析。结果胎心监护异常曲线252例（10．86％）。149例考虑胎儿窘迫行剖宫产术（59．13％）。结论产前产时胎心异常曲线对胎儿窘迫的诊断具有重要价值。     

胎心率远程监护系统的中心站设计

本文介绍了一种基于电话网的胎心率远程监护系统,它主要由前端胎心率检测仪、医院中心站组成。中心站通过Ｍｏｄｅｍ和公共电话网接收前端胎心率检测仪的数据,并对数据进行计算机辅助分析,在医生的参与下完成诊断过程。     

基于经腹胎儿心电技术的胎心率记录质量分析

目的研究基于母亲腹部胎儿心电(fetal electrocardiogram,f ECG)提取技术的便携式胎儿/母体心率记录仪Monica AN24行连续监护的胎儿心率记录质量(recording quality,RQ),以验证和评价f ECG技术采集非产时胎儿心率的可行性以及准确率。方法将98例孕36~41+6周的孕妇纳入本研究,使用胎儿/母体心率记录仪Monica AN24连续记录15 h胎儿心率数据,记录每小时以及15 h平均记录质量;当RQ≥60%时,定义记录质量良好。结果 16.8%的病例出现单小时RQ低于60%,100%病例在连续15 h监护时间内RQ≥60%。不同时段RQ总体具有统计学差异,P0.001,在夜间(4:00 am-5:00am)RQ达到最大值(98.6%±4.2%)。在该时段,不同孕周RQ、高危与无合并症孕妇RQ在组间不存在统计学差异;RQ与孕妇BMI、孕妇腹围、胎儿体重不存在显著相关性。结论采用f ECG技术可获得良好的RQ,在夜间4:00 am-5:00 am时间段达到最高值,且RQ不受孕周、孕妇BMI及孕妇腹围等因素影响,可作为连续监护高危胎儿心率的有效方法。     

The information content of Doppler ultrasound signals from the fetal heart

Knowledge of the content of Doppler ultrasound signals from the fetal heart is essential if the performance of fetal heart rate (FHR) monitors based upon this technology is to be improved. For this reason instrumentation was constructed to enable the simultaneous collection of Doppler audio signals and the transabdominal fetal ECG (for signal registration), with a total of 22 recordings being made with an average length of around 20 minutes. These data demonstrate the transient nature of the Doppler audio data with wide variations in the signal content observable on a beat-to-beat basis. Short-time Fourier analysis enabled the content of the Doppler signals to be linked to six cardiac events, four valve and two wall motions, with higher frequency components being associated with the latter. This differing frequency content together with information regarding the direction of movement that can be discerned from Doppler signals provided a potential means of discriminating between these six events (which are unlikely to all contribute to the Doppler signal within the same cardiac cycle). Analysis of 100 records showed that wall contractions generate the most prominent signals, with atrial contraction recognisable in all records and ventricular wall contraction in 95% (although its amplitude is only around 30% of that of the atrial signal). Valve motion, with amplitudes between 15 and 25% that of the atrial wall signal, were visible in 75% of records. These results suggest means by which the six events that contribute to the Doppler signal may be distinguished, providing information that should enable an improvement in the current performance of Doppler ultrasound-based FHR monitors.     

胎儿心率变异功率谱与胎儿宫内窘迫关系探讨

作者利用自行设计的胎儿心率变异检测分析系统采集的248例临床监护数据，研究胎儿心率变异（FHRV）功率谱的特征，对其中距分离时间1周以内的150例数据（睡眠期52例和活跃期98例），以谱参数为特征变量，窘迫值为分类变量，建立判别函数，作判别统计分析，通过跟踪病历对结果作回顾性考核，其判别准确率分别达88.5%(睡眠期）和83.3%(活跃期），显示FHRV功率谱特征与胎儿宫内窘迫有密切的关系。     

The event synchronous canceller algorithm removes maternal ECG from abdominal signals without affecting the fetal ECG

Fetal monitoring using abdominally recorded signals (ADS) allows physicians to detect occurring changes in the well-being state of the fetus from the beginning of pregnancy. Mainly based on the fetal electrocardiogram (fECG), it provides the long-term fetal heart rate (fHR) and assessment of the fetal QRS morphology. But the fECG component in ADS is obscured by the maternal ECG (mECG), thus removal of the mECG from ADS improves fECG analysis. This study demonstrates the performance of the event-synchronous interference canceller (ESC) in mECG removal from ADS data, recorded during pregnancy and labor. Its advantage as a compensation method for extended ADS processing is discussed.     

A PC-aided optical foetal heart rate detection system

Safe monitoring of foetal heart rate is a valuable tool for the healthy evolution and wellbeing of both foetus and mother. This paper presents a non-invasive optical technique that allows for foetal heart rate detection using a photovoltaic infrared (IR) detector placed on the mother’s abdomen. The system presented here consists of a photoplethysmography (PPG) circuit, abdomen circuit and a personal computer equipped with MATLAB. A near IR beam having a wavelength of 880?nm is transmitted through the mother’s abdomen and foetal tissue. The received abdominal signal that conveys information pertaining to the mother and foetal heart rate is sensed by a low noise photodetector. The PC receives the signal through the National Instrumentation Data Acquisition Card (NIDAQ). After synchronous detection of the abdominal and finger PPG signals, the designed MATLAB-based software saves, analyses and extracts information related to the foetal heart rate. Extraction is carried out using recursive least squares adaptive filtration. Measurements on eight pregnant women with gestational periods ranging from 35–39 weeks were performed using the proposed system and CTG. Results show a correlation coefficient of 0.978 and a correlation confidence interval between 88–99.6%. The t test results in a p value of 0.034, which is less than 0.05. Low power, low cost, high signal-to-noise ratio, reduction of ambient light effect and ease of use are the main characteristics of the proposed system.     

第一产程胎心监护异常226例的相关因素分析

目的探讨第一产程胎心监护异常的相关因素,提示处理措施。方法2004年1月1日至2004年12月31日对深圳市宝安区妇幼保健院226例第一产程胎心监护异常的相关因素进行回顾性分析。结果第一产程胎心监护异常为综合因素所致,胎儿高危因素为91.59%,母体高危因素为65.49%,产程处理因素为42.92%。结论第一产程胎心监护异常主要与胎儿因素、母体因素有关,提高产前检查质量,加强产程监护,正确选择分娩方式极为重要。     

Comprehensive fetal monitoring by microcomputer—A clinical approach

An inexpensive microcomputer has been devised to analyze fetal heart signals and fetal activity which were simultaneously recorded. Digital techniques were used to provide quantitative analysis of each of these inputs, and the interrelations among them. A parallel graphical presentation of those inputs was also provided.     

Influence of gestational age, heart rate, gender and time of day on fetal heart rate variability

From adult data, it is known that numerous factors, such as age, state of the autonomic nervous system, diurnal rhythms or mean R-R intervalmRR, influence heart rate variability (HRV). The aim of this study was the examination of the influence of gestational age,mRR, gender and time of day on fetal HRV. The analysis was based on 66 fetal magnetocardiograms (FMCGs) of 22 healthy fetuses between the 16th and 42nd week. FMCGs were recorded for 5 min using a multichannel biomagnetometer. On the basis of the time series of fetal R-R intervals,mRR as well as the standard deviationsdRR, root mean square of successive differencesrmssdRR and approximate entropyApEn were calculated. The influence of gestational age,mRR and gender onsdRR, rmssdRR andApEn was determined by regression analysis. The relationship between time of day and HRV was evaluated by visual inspection of scatterplots. The logarithmised HRV measures increased significantly with the logarithm of gestational age (regression coefficients:sdRR=1.28,rmssdRR=1.12,ApEn=1.30) andmRR (regression coefficients:sdRR=0.008,rmssdRR=0.011,ApEn=0.012) There was no significant influence of gender. With respect to time of day (between 0800 h and 1800 h), no dependency of the HRV measures was apparent. In summary, when fetal HRV is assessed, it is essential to take gestational age andmRR into account. In contrast, time of day, with respect to daytime, and gender need not be considered. In future studies, the influence of fetal activity state on HRV should be examined.     

Applicability of adaptive noise cancellation to fetal heart rate detection using photoplethysmography

In this paper, an approach based on adaptive noise cancellation (ANC) is evaluated for extraction of the fetal heart rate using photoplethysmographic signals from the maternal abdomen. A simple optical model is proposed in which the maternal and fetal blood pulsations result in emulated signals where the lower SNR limit (fetal to maternal) is -25dB. It is shown that a recursive least-squares algorithm is capable of extracting the peaks of the fetal PPG from these signals, for typical values of maternal and fetal tissues.     

基层医院胎儿先天性心脏病超声筛查的价值

目的探讨在基层医院对胎儿严重先天性心脏病进行超声筛查的价值。方法对1754例胎儿进行八个心脏切面的检测。结果共检出严重先天性心脏病9例,并经证实,真阳性率100%。结论在基层医院开展胎儿严重心脏超声筛查可行,对优生优育有重要意义。     

Detection of fetal breathing and cardiac movements and rhythms in ultrasonic Doppler signal recorded on the surface of the maternal abdomen

It is proposed to use information on the direction of reflector movement and extensive filtering in the detection of fetal breathing and cardiac movements in the ultrasonic Doppler signal recorded on the surface of the material abdomen. The method appears fairly insensitive to spurious signals and allows those of interest to be distinguished without any reference technique. A decision rule for breathing and cardiac rhythm detection, incorporating movement direction, amplitude, shape and periodicity criteria, is also proposed.     

脐带穿刺时胎心过缓的处理-经母腹胎儿胸廓按压法

目的探索脐带穿刺时胎儿过缓的新的处理方法-经母腹胎儿胸廓按压法.方法比较A组未经母腹胎儿胸廓按压法和B组经母腹胎儿胸廓按压法使脐带穿刺时胎心过缓的胎儿心率恢复的快慢.结果在580人次的脐带穿刺中,共32人次的孕妇胎心率出现过缓,发生率为5.5%.B组20你出现胎心率过缓恢复时间平均是69±21s,A组12例胎心率过缓时间平均是156±45s,B组胎心率恢复明显快于A组,两组差异有显著性(P＜0.05).结论经母腹胎儿胸廓按压法可能是脐带穿刺时胎心过缓的新的处理方法之一.     

The influence of cognitive load on maternal postural sway and heart rate in response to infant vocalizations

Infants communicate their emotions to their caregivers through cries and laughter. Recent work suggests that adaptive parenting requires cognitive regulation of intuitive behaviors toward infants’ signals. In this study, we examined the effects of cognitive regulation on mothers’ unconscious behavioral and cardiac responses to infant cries and laughs. In all, 55 mothers took part in this study. To manipulate cognitive load, mothers were asked to memorize alphabet characters (two letters in the low cognitive load condition and eight in the high cognitive load condition). Then, they heard infant vocalizations (cries or laughs) for 6 s. During this time, we measured mothers’ behavioral (center of pressure, an index of approach–avoidance behavior) and physiological (heart rate) responses. Regardless of vocalization type (infant cries or laughs), high cognitive load increased mothers’ forward movement toward the infant sounds as well as mothers’ heart rate. These findings advance our understanding of the link between executive function and maternal response to infant signals by utilizing postural and physiological measures of maternal response during memory tasks that require cognitive resources.     

Computation of short-term fetal heart-rate variability from heart-rate waveforms

Fetal heart-rate monitoring during labor is now routine in high-risk pregnancies. Beat-to-beat, or short-term variability in the heart rate has aroused considerable recent attention and several quantitative indices based on the fetal electrocardiogram have been proposed. These cannot be implemented on micro- or mini- computer-based labor-room systems without additional hardware because of the ECG processing involved. This paper describes a procedure for computing short-term variability from heart-rate waveforms. It correlates excellently with the above methods, but can be implemented on a microcomputer without special interfacing, since it uses only the slowly-varying heart-rate waveform.