Decreased fetal movements at home were recorded by a newly developed fetal movement recorder in a case of a non-reassuring fetal status

Abstract

A fetal movement acceleration measurement (FMAM) recorder was developed for home monitoring of fetal movements. We provided a 32-year-old pregnant woman with the FMAM recorder to home monitor fetal movements, thereby self-recording decreased fetal movements at 30 weeks’ gestation. On routine checkup, a non-stress test revealed scant fetal heart rate accelerations. At 31 weeks’ gestation, the woman underwent an emergent caesarean delivery because of a non-reassuring fetal heart rate pattern, and delivered a female neonate weighing 1312?g, whose umbilical cord was slightly narrowed at the umbilicus. Our experience with the present case suggests the usefulness of the FMAM recorder.     

Antenatal evaluation of FHR accelerations associated with fetal movements

A retrospective comparative study of two definitions of the non-stress testing employing two and four accelerations associated with fetal movements in 20-min observation in 304 high risk pregnant women was evaluated. It was shown that four accelerations or more are no more predictive of good outcome than two accelerations during the same period. On the other hand a non-reactive test is significantly more predictive of poor outcome when two acceleration definition was employed. It was shown in cases with good outcome that the reactivity of the non-stress test increases with gestational age and that this test is invalid prior to the 33rd week of gestation.     

Quantitative and Qualitative Relationships Between Fetal Heart Rate Accelerations and Fetal Movement

We measured duration, amplitude, and duration at peak amplitude of 117 heart rate accelerations of 12 normal fetuses greater than 36 weeks gestation. Fetal movement measured by Doppler was analyzed for duration of movement; number of limb, spine, and rolling movements; and total movements per epoch of movement. Of 117 accelerations, only five were not associated with recorded movement and all of these had amplitude less than 12 bpm and duration less than 16 seconds. Only four (3%) accelerations occurred before fetal movement was detected, 23 (20%) began after onset of movement, and the large majority (77%) of fetal heart rate (FHR) accelerations occurred synchronously with fetal movement. In addition to an obvious correlation between number of movements and time spent in movement, a relationship exists between movements and duration of accelerations. Movements do not correlate with amplitude of accelerations. Fetal movement and heart rate acceleration relate temporally, but the strength or type of movements does not affect the amplitude of accelerations. This supports the argument that FHR accelerations are not directly mediated by quantity or quality of fetal movement, but that either all or none of the responses or central mechanisms are involved.     

A Case Report of Decreased Fetal Movement During Fetomaternal Hemorrhage

Fetomaternal hemorrhage is a rare, potentially catastrophic event for a fetus. Leakage of the fetus’s blood into the mother’s circulation can cause fetal anemia, hydrops, and even death. The prevailing symptom is decreased fetal movement, and signs can include a sinusoidal electronic fetal monitor pattern, a positive Kleihauer-Betke test, or changes in fetal Doppler blood flow. A mother’s report or perception of decreased fetal movement coupled with a nonreactive nonstress test or abnormal ultrasound findings should prompt an investigation into underlying causes.     

Hemodynamic changes in the fetal arteries during the second half of pregnancy assessed by Doppler velocimetry

The applicability of Doppler velocimetry has been well established regarding intrauterine growth restriction and fetal hypoxia. This method can also be used to determine fetal anemia and cardiac malformations. The main fetal arteries evaluated by Doppler velocimetry are the middle cerebral artery and the umbilical artery. However, the fetal aorta is responsible for the distribution of blood flow to the upper and lower extremities of the human body and should also be properly valued. In order to characterize abnormalities in the arteries of high-risk fetuses, it is necessary to know the hemodynamic modifications of normal fetuses. On this basis, the authors performed a review of fetal hemodynamics evaluated by Doppler velocimetry in the fetal aorta and middle cerebral and umbilical arteries during the second half of pregnancy. The study of fetal vessels by Doppler velocimetry indirectly evaluates the hemodynamic changes occurring in fetuses at risk. In this respect, we emphasize the changes in Doppler velocimetry occurring in fetal anemia, in restricted intrauterine growth, and in normal fetuses.     

Non-stress test changes during acupuncture plus moxibustion on BL67 point in breech presentation

OBJECTIVES: We assessed fetal heart variability and activity using a computerized non-stress test (NST) during acupuncture plus moxibustion on the BL67 point. For comparison, the same changes were assessed during placebo acupuncture (minimal acupuncture) in the same subjects. METHODS: Twelve pregnant women in the 33rd week of gestation, carrying singletons in the breech presentation were enrolled in the study. In a single-blind design, each woman received a first session of minimal acupuncture followed 1-2 days later by true acupuncture. During the sessions, women were monitored using computerized non-stress testing starting 20 minutes before the stimuli and continuing for 20 minutes after treatment. RESULTS: During true acupuncture a significant reduction in fetal baseline heart rate, and more accelerations and movement were observed. During minimal acupuncture, there were no significant changes in these variables. No signs of fetal distress or changes in short- or long-term variability were noted, and there were no uterine contractions. CONCLUSION: In our study population, acute application of acupuncture plus moxibustion did not cause fetal distress as assessed by either fetal heart rate decelerations or changes in either short- or long-term variability. Considering that the modifications in fetal movement and heart rate occurred in true but not during minimal acupuncture, we could consider that such changes are related to the effect of the acupuncture stimulation. The mechanisms leading to the cephalic version remain to be clearly established.     

Computer processing of the ultrasonic Doppler actographic fetal movement signals

Computer analysis of ultrasonic Doppler actographic signals was done in the fetal active state, resting state and during fetal breathing movement (FBM) in order to more objectively study fetal movements. 1) The amplitude and interval of movement signal spikes were analyzed in 11 voltage steps between 0.05 and 0.55V. The interval distribution showed a uniform pattern in all states when the signals were analyzed at levels below 0.10V. 2) In the fetal resting state, almost all spikes were distributed in the lowest level of amplitude. 3) In the fetal active state, the mean values for spike amplitude were high and the coefficients of variation (CV) were large. The 3-dimensional interval number histograms showed wide distribution until high amplitude and long interval steps. 4) In FBM, the mean values for spike amplitude and CV were smaller, respectively, than those in the active state and the spikes distributed in the short interval steps of 0.5-2.0 seconds. 5) The envelope processing was useful for easier recognition of fetal movement burst in the fetal active state. A very low envelope was formed in the resting state. Analyses during FBM revealed a flat but elevated envelope. The results show the possibility of automatic and objective recognition of fetal behavioral states.     

胎儿大脑中动脉血流在高危妊娠中应用价值的研究进展

胎儿大脑中动脉（MCA）是胎儿大脑血流供应最丰富的血管,对反映胎儿脑部血液循环改变及血氧情况的变化有重要的临床应用价值。正常妊娠时,随着孕周增加,胎儿脑部发育逐渐完善,胎儿MCA彩色多普勒超声血流信号指标的变化呈抛物线模式。在高危妊娠中,胎盘功能不足、血管阻力增加与不良妊娠结局之间呈一定的相关性。MCA具有自身调节功能,当胎儿的内外环境出现变化时如缺氧等可导致MCA的血流动力学发生改变,而胎儿MCA彩色多普勒超声的各项血流信号指标也呈异常的变化趋势。彩色多普勒超声检查胎儿MCA血流动力学指标对母儿双方安全、无创、方便以及可重复性高,可用来反映胎儿的一系列病理生理改变,成为近年来临床评估胎儿生长发育和宫内安危状况的重要监测手段。。     

Fetal arterial redistribution indicating true umbilical cord knot

True umbilical cord knot often remains undiscovered prenatally due to a lack of characteristic clinical or ultrasound signs. We present a pregnancy with favorable outcome in which a non-stress test (NST) found non-reassuring fetal status. Abnormal Doppler blood flow patterns in the descending aorta and in the middle cerebral artery revealed fetal arterial redistribution with normal circulation in the umbilical artery despite a true cord knot. The benefit of fetal Doppler assessment is discussed. Increased aortic-cerebral ratio may reflect acute hypoxic compromise caused by the transitory constriction of the true umbilical cord knot with unrecognized morphologic and circulatory signs.     

Antepartum fetal assessment in hypertensive pregnancies.

Antepartum fetal assessment in hypertensive pregnancies helps to prevent perinatal morbidity and mortality. The pathophysiology of chronic maternal hypertension often leads to placental insufficiency and fetal growth retardation. Current testing schemes include serial ultrasonographic assessment of fetal growth, placental morphology, and amniotic fluid volume; fetal heart rate testing using either non-stress or contraction stress methods; multiple parameter biophysical profile; and Doppler flow velocimetry of fetal umbilical and maternal uterine arteries. The values of individual and combined testing approaches are evaluated and an integrated scheme for fetal management, illustrated by case examples, is presented.     

电话远程胎儿监护系统的临床应用

目的 评价电话远程胎儿监护系统的临床应用价值,探索孕妇家庭自我监护的新途径。方法将２０４例妊娠合并贫血、糖尿病、溶血、肾脏疾病、胎儿宫内发育迟缓、妊高征的孕妇、分为试验组（９７例）和对照组（１０７例）。试验组以是锭程胎儿监护系统结合胎动计数进行自我     

Detection of fetal movement using Doppler ultrasound

Using conventional cardiotocographic equipment with the ultrasound transducer placed to detect the fetal heart, we obtained unprocessed Doppler signals in the frequency range 13-70 Hz and used them to detect movements of the fetal trunk. In an assessment of maternal perception of fetal activity, we found that Doppler signals were associated with 739 of 780 appreciated movements (95%); however, 36% of all the Doppler signals were unaccounted for. A separate comparison of the Doppler signals against real-time ultrasound observations of fetal activity showed that 913 of 970 visualized trunk movements (94%) were associated with Doppler signals. Other Doppler signals were found to be due principally to fetal breathing and fetal hiccups. Appropriate processing of the Doppler signals obtained during antenatal cardiotocography may allow an objective assessment of fetal activity to be added to the fetal heart rate recording.     

静脉多普勒流速曲线与胎儿循环的研究

以往在对胎儿循环的研究中,只有动脉多普勒流速曲线。近几年静脉多普勒流速曲线的研究逐渐成为重点和热点。胎儿心脏后负荷、心肌顺应性、血容量及心率改变可以调节静脉和动脉的血流速度波形。心血管因素的改变常见于严重的胎儿生长受限、双胎输血综合征、胎儿水肿等。阐述上述胎儿病理情况下静脉导管、下腔静脉、脐静脉等的多普勒流速曲线的变化。静脉多普勒评估可提供关键性的诊断及预后信息,并对指导临床治疗起重要作用。故而全面的多普勒评估应包括静脉多普勒评估。     

胎儿生长受限对胎儿脑神经发育的影响

胎儿生长受限（fetal growth restriction,FGR）可引起胎儿及新生儿近远期发育异常和成年期的严重神经系统疾病,因此FGR对胎儿及新生儿脑神经发育的影响已成为近年来的研究热点。人类研究和动物实验结果显示,FGR的发病时间、FGR的严重程度和分娩时孕周与胎儿脑神经发育密切相关。大脑中动脉多普勒超声、脑-胎盘率可评估FGR胎儿脑血流动力学,相位对比磁共振成像可监测胎儿脑血流及脑结构。早发型和晚发型FGR对子代脑神经发育的影响不同,FGR还可导致胎儿脑结构和功能异常,脑室内出血发生率增加。综述FGR对胎儿脑神经发育影响的研究进展,以期加强临床对FGR胎儿的管理,改善其近远期结局。     

Analysis of fetal movements by Doppler actocardiogram and fetal B-mode imaging

We have presented that fetal surveillance may be enhanced by use of the fetal actocardiogram and by computerized processing of fetal motion as well as fetal B-mode ultrasound imaging. Ultrasonic Doppler fetal actogram is a sensitive and objective method for detecting and recording fetal movements. Computer processing of the actograph output signals enables powerful, detailed, and convenient analysis of fetal physiologic phenomena. The actocardiogram is a useful measurement tool not only in fetal behavioral studies but also in evaluation of fetal well-being. It reduces false-positive, nonreactive NST and false-positive sinusoidal FHR pattern. It is a valuable tool to predict fetal distress. The results of intrapartum fetal monitoring are further improved by the antepartum application of the actocardiogram. Quantified fetal motion analysis is a useful, objective evaluation of the embryo and fetus. This method allows monitoring of changes in fetal movement, as well as frequency, amplitude, and duration. Furthermore, quantification of fetal motion enables evaluation of fetal behavior states and how these states relate to other measurements, such as changes in FHR. Numeric analysis of both fetal actogram and fetal motion from B-mode images is a promising application in the correlation of fetal activity or behavior with other fetal physiologic measurements.     

Behavioral parameters assessing human fetal development

Fetal behaviors gradually integrate into more complex movements in relation to each other along with functional central nervous system development. Investigating the ontogenesis of fetal behavior made it possible to allow prenatal localization of functional brain impairment, however, it is still difficult to deduce higher brain function in human fetuses.

Fetal learning has the potential to be a new parameter to deduce higher brain function in the human fetus. We investigated fetal learning from a behavioral development perspective assessed by a conventional parameter, i.e. eye movement patterns. After at least 32 weeks of gestation, the fetuses presented habituation to vibro-accoustic stimulation. Fetuses less developed required significantly more trials to show habituation than developed fetuses from a behavioral standpoint even at the same gestational age. Three- or four-dimensional ultrasound evaluation also provides new findings in fetal behaviors in early gestation.

These methods could be new parameters to assess fetal brain function, however, it is necessary to choose appropriate parameters and to develop easy and ubiquitous criteria, which cover higher brain function throughout the entire gestational stage.     

Evaluation of maternal perception of sound-provoked fetal movement as a test of antenatal fetal health

Maternal perception of sound-provoked fetal movement was correlated with the results of nonstress cardiotocography in 1097 women with obstetric or medical antenatal risk factors. Ninety-two percent of the mothers felt fetal movements with the stimulus; all but three had a reactive non-stress test (NST). These three women were taking multiple antihypertensive drugs and were less than 33 weeks' gestation. Of 88 patients with no maternal perception of sound-provoked fetal movement, ten had nonreactive NSTs. Ultrasound confirmed the absence of fetal movement to the stimulus. The outcome in nine of these ten cases suggested some evidence of fetal compromise. Maternal perception of sound-provoked fetal movement correlated well with the results of the NST; the sensitivity (76.9%), specificity (92.8%), and negative predictive value (99.7%) were all high, although the positive predictive value was only 11.4%. Maternal perception of sound-provoked fetal movement may suffice as an inexpensive and simple method of evaluating antenatal fetal well-being in risk situations. When the mother is doubtful or does not feel the sound-provoked fetal movement, NST is indicated to evaluate the fetal health.     

Venous Doppler evaluation of the growth-restricted fetus

Evaluation of venous Doppler parameters has significantly contributed to the understanding of the vascular mechanisms that lead to fetal growth restriction (FGR) and subsequent fetal deterioration in the setting of progressive placental dysfunction. Venous redistribution of umbilical venous blood flow away from the fetal liver precedes fetal growth delay. Venous Doppler examination allows adjustment of monitoring intervals in recognition of accelerating fetal deterioration. The timing of delivery in early-onset FGR remains challenging because gestational age has an overriding effect on the neonatal outcome until the late second trimester and randomized trials of specific delivery triggers are lacking.     

Aortic isthmus and cardiac monitoring of the growth-restricted fetus

Aortic isthmus acts as an arterial watershed between the cerebral and placental circulations, connecting 2 parallel fetal ventricular pumps. It plays a crucial role in the fetal circulatory dynamics. Information about aortic isthmus blood flow may improve the management of sick fetuses. However, perceived technical difficulties limit the clinical use of aortic isthmus Doppler for fetal hemodynamic monitoring. Changes in aortic isthmus blood flow pattern seem to reflect fetal cardiovascular status accurately and predict perinatal and long-term neurodevelopmental outcome in intrauterine growth restriction. This review evaluates the available scientific information and discusses the role of aortic isthmus in fetal circulation.     

Transvaginal pulsed Doppler velocimetry in fetal arteries

Summary Transabdominal pulsed Doppler velocimetry in fetal arteries might be difficult with extreme obesity, anhydramnios, cord presentation and an unfavourable position of the fetal head. A vaginal transducer gets closer to the presenting part of the fetus and therefore has advantages for Doppler velocimetry in fetal arteries.