Fetal Body Movements Research Articles

Fetal respiratory movements improve reliability of heart rate variability and suggest a coupling between fetal respiratory arrhythmia and vagal activity.

Fetal heart rate variability (FHRV) reflects autonomic cardiac regulation. The autonomic nervous system constantly adjusts the heart rate to maintain homeostasis. By providing insight into the fetal autonomic state, FHRV has the potential to become an investigational and clinical instrument. However, the method needs standardization and the influence of fetal movements, including fetal respiratory movements, is not well explored. Therefore, in a highly standardized setting, the aim was to evaluate the association between fetal movements and fetal heart rate variability (FHRV) including their impact on reliability. Fetal heart rate was obtained by noninvasive fetal electrocardiography (NI‐FECG) and fetal movements by simultaneous ultrasound scanning in 30 healthy singleton pregnant women on two occasions with a maximum interval of 7 days. The standard deviation of normal‐to‐normal RR‐intervals (SDNN), root mean square of successive RR‐interval differences (RMDDS), high‐frequency power (HF‐power), low‐frequency power (LF‐power), and LF/HF were measured. A multivariate mixed model was used and reliability was defined as acceptable by a coefficient of variance (CV) ≤15% and an intraclass correlation coefficient (ICC) ≥0.80. During time periods with fetal respiratory movements, the highest reliability was achieved. Intra‐ and inter‐observer reliability measurements were very high (CV: 0–9%; ICC ≧ 0.86). Within the same recording, SDNN and RMSSD achieved acceptable reliability (CV: 14–15%; ICC ≧ 0.80). However, day‐to‐day reliability displayed high CV’s. In time periods with fetal respiratory movements, as compared to periods with quiescence RMSSD and HF‐power were higher (Ratio: 1.33–2.03) and LF/HF power lower (Ratio: 0.54). In periods with fetal body movements SDNN, RMSSD and HF‐power were higher (Ratio: 1.27–1.65). In conclusion, time periods with fetal respiratory movements were associated with high reliability of FHRV analyses and the highest values of parameters supposed to represent vagal activity.

ANTENATAL BETAMETHASONE COMPARED WITH DEXAMETHASONE IN TERMS OF FETAL HEART RATE VARIABILITY AND FETAL BODY MOVEMENTS

Introduction: Preterm labor occurs between 20th and 37th gestational week which is regardless of the birth weight. The incidence of preterm birth is increasing and continues to be the leading cause of neonatal mortality and morbidity. Antenatal corticosteroids are used for pregnant women at risk of preterm labor to reduce fetal mortality and morbidity by increasing fetal lung maturation and preventing the fetus from respiratory distress syndrome. In this study, we aimed to evaluate the effects of antenatal dexamethasone and betamethasone on fetal heart rate variability and fetal body movements. Material and method: The pregnant women applied to clinic due to the risk of preterm labor between November 2003 and May 2004 hospitalised due to the risk of preterm labor and tocolytic treatment. The glucocorticoids to be initiated and to provide lung maturation were included in the study. Included in the study pregnant women were randomly divided into two groups. 24 hours for 20 pregnant women in the first group, 12 mg betamethasone was administered intramuscularly. 20 in the second group 6 mg dexamethasone was administered intramuscularly every 12 hours. NSTs for later evaluation of fetal well-being and baby movements were compared. Results: Pregnant women in betamethasone and dexamethasone groups compared in terms of age, gravida, parity and gestational week, there was no significant difference between the two groups (p> 0.05). At the time of first glucocorticoid application (onset) and 24 hours after the last dose of betamethasone/dexamethasone therapy, fetal heart rate, acceleration, deceleration and fetal movement counts were calculated for 3 days in the morning and evening. A significant increase was observed at heart rate in the betamethasone group after treatment, but there was no change in basal heart rate in the dexamethasone group. In the number of acceleration; significant increase was observed in betamethasone group while there was no statistically significant change was observed in the dexamethasone group. Fetal body movements were changed significantly in both groups compared with the basal movements. Conclusion: Antenatal glucocorticoid application (especially betamethasone) caused a temporary suppression in the NST and fetal movements that were used to determine fetal well-being. It should be kept in mind that these temporary changes may be misdiagnosed as fetal distress. Both dexamethasone and betamethasone can be applied in preterm delivery as a safe manner.

First evidence that intrinsic fetal heart rate variability exists and is affected by hypoxic pregnancy.

We introduce a technique to test whether intrinsic fetal heart rate variability (iFHRV) exists and we show the utility of the technique by testing the hypothesis that iFHRV is affected by chronic fetal hypoxia, one of the most common adverse outcomes of human pregnancy complicated by fetal growth restriction. Using an established late gestation ovine model of fetal development under chronic hypoxic conditions, we identify iFHRV in isolated fetal hearts and show that it is markedly affected by hypoxic pregnancy. Therefore, the isolated fetal heart has intrinsic variability and carries a memory of adverse intrauterine conditions experienced during the last third of pregnancy. Fetal heart rate variability (FHRV) emerges from influences of the autonomic nervous system, fetal body and breathing movements, and from baroreflex and circadian processes. We tested whether intrinsic heart rate variability (iHRV), devoid of any external influences, exists in the fetal period and whether it is affected by chronic fetal hypoxia. Chronically catheterized ewes carrying male singleton fetuses were exposed to normoxia (n=6) or hypoxia (10% inspired O2 , n=9) for the last third of gestation (105-138days of gestation (dG); term ∼145dG) in isobaric chambers. At 138dG, isolated hearts were studied using a Langendorff preparation. We calculated basal intrinsic FHRV (iFHRV) indices reflecting iFHRV's variability, predictability, temporal symmetry, fractality and chaotic behaviour, from the systolic peaks within 15min segments in each heart. Significance was assumed at P<0.05. Hearts of fetuses isolated from hypoxic pregnancy showed approximately 4-fold increases in the Grid transformation as well as the AND similarity index (sgridAND) and a 4-fold reduction in the scale-dependent Lyapunov exponent slope. We also detected a 2-fold reduction in the Recurrence quantification analysis, percentage of laminarity (pL) and recurrences, maximum and average diagonal line (dlmax, dlmean) and the Multiscale time irreversibility asymmetry index. The iHRV measures dlmax, dlmean, pL and sgridAND correlated with left ventricular end-diastolic pressure across both groups (average R2 =0.38±0.03). This is the first evidence that iHRV originates in fetal life and that chronic fetal hypoxia significantly alters it. Isolated fetal hearts from hypoxic pregnancy exhibit a time scale-dependent higher complexity in iFHRV.

Advanced automatic detection of fetal body movements from multichannel magnetocardiographic signals

Objective: Both heart rate (HR) monitoring and detection and description of fetal movements provide essential information of the integrity of in utero development and fetal wellbeing. Our previously described method to identify movements from multichannel magnetocardiographic (MCG) recordings lacks of reliability in some cases. This work is aimed at the improvement of fetal movement detection by means of an advanced signal processing and validation strategy. Approach: The previously proposed methodology of fetal body movement detection from MCG recordings using single space angle (SSA), min–max amplitude (MMA) and a measure of the overall signal strength across (RSS) was extended by moving correlation coefficient (MCC). The methodology was developed with respect to the discrimination between active and quiet sleep, validated by testing its coupling with HR accelerations in a total of 137 recordings lasting 30 min from 98 fetuses aged 34–38 weeks of gestation (WGA) of normal pregnancy. Main results: The developed algorithm improves the reliable automatic detection of fetal body movements independent of the fetal sleep states and their changes in the individual MCG recordings. In the fetuses aged 34–38 WGA 94% of 15 × 15 HR accelerations were coupled with detected movements. The visual inspection of the movement graphs of 30 fetuses aged 20–32 WGA supports the transferability of the movement detector to this age. In four subjects MCG-based movement detection and maternal report on percepted fetal movements were consistent. Significance: The presented methodology allows the parallel automatic acquisition of precise fetal heart rate variability (HRV) indices based on subsequent beat intervals and of fetal body movements from MCG recordings during late 2nd and 3rd trimester. Potential advantages of parallel monitoring of fetal HRV and movements using MCG compared to established ultrasound technology should be investigated in subsequent studies with respect to the identification of fetuses at risk.

The Impact of Maternal Voice on the Fetus: A Systematic Review

Background: Studies have shown pre-natal memory underlining the ability of newborns to discriminate maternal vs. other voices and to recognize linguistic stimuli presented prenatally by the mother. The fetus reacts to maternal voice at the end of gestation but it is important to clarify the indicators and conditions of these responses. Objective: To understand the state of the art concerning: 1) indicators of fetal reactions to maternal voice vs. other voices; 2) conditions of maternal voice required to obtain fetal response, 3) neonatal recognition of maternal voice and of linguistic material presented prenatally and 4) obstetric and behavioral maternal conditions compromising fetal ability to discriminate between maternal and other female voices. Method: Systematic review using EBSCO, WEBSCIENCE and MEDLINE. Eligibility: studies with maternal voice delivered before birth as stimulus and with fetal or neonatal behavior as responses. Results: Fetal responses to maternal voice are observed through fetal cardiac, motor (fetal yawning decrease, mouth opening, fetal body movements) and brain responses (activation of the lower bank of the left temporal lobe). Newborns’ head orientation and non-nutritive sucking are shown as being neonatal indicators. Conclusion: Gestational age, baseline measures (fetal state, acoustic conditions and pre-stimulus time) and obstetrical conditions may enable or compromise fetal discrimination between maternal and other voices. The role of maternal voice for prenatal human bonding needs to be discussed according to different maternity conditions such as surrogate mothers. A new paradigm is suggested; the focus of research should be on maternal-fetal interaction under the presence of maternal voice.&lt;/P&gt;

Effect of Fetal Movements and Fetal Breathing on Fetal Middle Cerebral Artery Pulsatility Index Measurement

Objective: This study aimed to determine the effect of fetal movements on the MCA pulsatility index (PI) and quantify the fall of MCA PI after initiation of fetal movements and/or breathing, and the time taken to recover from a fall below the 5th percentile. Methods: 16 women with appropriate for gestational age (AGA) fetuses and 16 women with small for gestational age (SGA) fetuses were recruited. MCA PI during “no movement” state was compared with MCA PI values during fetal body movements and breathing movements. Results: MCA PI measurements with body or breathing movements were significantly (p < 0.005) lower as compared to that observed without movements. MCA PI started rising immediately after cessation of body movements and/or breathing movements. Conclusions: MCA PI with fetal body or breathing movements is significantly lower as compared to that observed in the quiet state. If MCA PI measurement is below 5th centile, it should be measured again up to 90 seconds after cessation of fetal body and/or breathing movements in order to minimize false positive diagnosis of cerebral sparing effect in SGA as well as AGA fetuses.

Does antenatal betamethasone have negative effects on fetal activities and hemodynamics in cases of preeclampsia without severe features? A prospective, placebo-controlled, randomized study

Aim: To evaluate whether antenatal betamethasone affects the fetal biophysical profile (BPP) and Doppler indices of umbilical and middle cerebral arteries (MCAs) in cases of preeclampsia without severe features. Materials and methods: Forty singleton preeclamptic pregnancies without severe features at gestational ages of 28–34 weeks were randomly divided into two groups of 20 patients: betamethasone and control groups. Patients in the betamethasone group were administered two consecutive doses of 12 mg betamethasone intramuscularly, 24 h apart, and patients in the control group were administered the same volume of saline as a placebo. All participants were evaluated before (0 h) and at hours 24, 48, and 72 of betamethasone/placebo administration using BPP scoring and umbilical and MCA Doppler examinations. Results: Total BPP scores were significantly lower in the betamethasone group across the three time points during the follow-up period (p < 0.001). None of the Doppler indices differed significantly between the groups (p > 0.05). Conclusion: Antenatal betamethasone negatively affects fetal BPP score parameters, including the non-stress test, fetal body and breathing movements, without affecting vascular indices of umbilical arteries and MCAs. Clinician awareness of this transient drug-induced effect might be valuable for preventing iatrogenic preterm delivery for fetuses in preeclamptic pregnancies without severe features.

Exploratory Study of the Relationship Between Maternal Body Mass Index and Spontaneous Fetal Movements

Maternal body mass index (BMI) has been reported to be associated with the number of fetal body movements and the duration of fetal breathing movements in hypertensive pregnant women (Brown et al., 2008). However, whether a relationship exists in pregnancies classified as overweight or normal weight but not complicated by hypertension is unknown and the focus of this study. Forty-five maternal-fetal pairs (normotensive, normal weight=15; normotensive, overweight=15; hypertensive=15) who had participated in a study of fetal behavior which included a 20 min real-time ultrasound scan observation of fetal movements were randomly selected from the laboratory archival database. Gestational age at testing ranged from 33-39 weeks [M(SD)= 36.2 (1.4) weeks]. All infants were delivered healthy at term. Video-recordings of the ultrasound scans were scored for the number of fetal body movements (interrater reliability r=.97) and the cumulative duration of breathing (interrater reliability r=.94) movements. The number of fetal body movements differed between groups, F(2,38)=3.19, p=0.05, with fetuses of overweight mothers moving less frequently than those of normal weight mothers (M=9.7 vs 15.5, respectively). Maternal BMI prior to pregnancy, r=-0.43, p&lt;0.01, and at time of observation, r=-0.44, p&lt;0.01, was associated with the number of fetal body movements, but not with duration of breathing movements. As BMI increased, the number of fetal body movements decreased. It was concluded that maternal BMI may affect the number of spontaneous fetal movements. A prospective study is necessary to determine whether BMI should be considered when using body movement counts to assess well-being and/or neurodevelopment.

Effect of Acetaminophen on Fetal Activity.

The aim of this study is to determine if maternal administration of acetaminophen affects fetal activity and thereby the interpretation of clinical assessments of fetal well being. A longitudinal study was performed in 20 women between 30 and 34 weeks' gestation with uncomplicated pregnancies. A 1-hour ultrasound was performed and recorded to document baseline fetal breathing and body movements. All the subjects were then given a 1,000 mg dose of oral acetaminophen. One hour later, a second 1 hour ultrasound was performed to document postacetaminophen fetal breathing and body movements. The number of episodes and total duration of gross body and fetal breathing movements were then assessed by a blinded observer. The pre- and post-acetaminophen values were compared using a repeated measures t-test. There was no significant effect of acetaminophen on the number of episodes or time spent in fetal breathing or body movements when each activity parameter was analyzed separately. In addition, there was no effect when fetal breathing and body movements were combined into a single composite activity score. Although acetaminophen has been shown to affect fetal activity in animal models, it has little effect on humans. Thus, maternal administration of acetaminophen should not affect assessment of fetal well being.

Noise reduction by perfect-translation-invariant complex discrete wavelet transforms for fetal electrocardiography and magnetocardiography

Echocardiography is widely used for the diagnosis of fetal cardiac arrhythmias. However, this method does not detect configurational changes in the electrocardiogram (ECG) such as life-threatening changes in QRS and the prolongation of the QT interval. Fetal magnetocardiography (fMCG) and fetal electrocardiography (fECG) are valuable tools for the detection of electrophysiological cardiac signals although both have certain limitations. Such techniques must deal with excess internal noise such as maternal respiratory movements, fetal movements, muscle contraction and fetal body movement and external noise (e.g., electromagnetic waves). Heart rate variability (HRV) is a well-known phenomenon with fluctuation in the time interval between heartbeats. The lack of translation invariance is a serious defect in the conventional wavelet transforms (discrete wavelet transform (DWT)). Fluctuation of the impulse response at each energy level is observed in the multi-resolution analysis (MRA). Configurational changes in the ECG waveforms are frequently observed after noise reduction by the conventional wavelet transforms. Both the lack of translation invariance of conventional wavelet transforms and HRV cause deformation of the ECG waveforms. We describe here the CDWTs with perfect translation invariance (PTI). Compared with conventional wavelets, PTI of the fECG and fMCG resulted in only minor configurational changes in the ECG waveforms. This technique yields persistently stable ECG waveforms, including P wave and QRS complex. First, an independent component analysis (ICA) was applied to fECG or fMCG data to remove noise. We provide an example to show that the morphological change in QRS complex is barely affected when PTI is applied to normal fECG. Examples of fetal arrhythmias, such as ventricular trigeminy, ventricular bigeminy and premature atrial contraction are demonstrated using this technique. The results lead us to the conclusion that ICA and noise reduction in fECG and fMCG by PTI are promising methods for the diagnosis of fetal arrhythmia.

Advanced dynamic Doppler flow of the pulmonary artery in a normal population: reference values from 18 to 41 weeks of gestation calculated by automatic Doppler waveform analysis

The aim of the present cross-sectional prospective study was to establish Doppler reference ranges for blood flow velocity waveforms (V max, V mean and V min) and resistance indices (PI, RI) of the fetal pulmonary arteries using the new pulsed-wave color advanced dynamic flow (ADF) Doppler technique. Data were collected in 206 low-risk pregnancies at 18-41 weeks of gestation. The measurements were obtained in the proximal pulmonary artery near the first bifurcation in the absence of fetal body or breathing movements. The pulsatility index (PI) in the pulmonary artery showed mean increases of 2.43-3.59 between gestational weeks 18 and 42. A similar pattern was observed for the resistance index (RI) with increases of 0.79-0.90. Increases in systolic (V max), mean (V mean) and end diastolic (V min) blood flow velocities of 36.0-63.3, 10.8-19.9 and 5.71-7.53 cm/s, respectively, were noted during the observation interval. The ranges for blood flow velocities and impedance indices in the fetal pulmonary artery calculated by the authors may serve as reference values to help distinguish a normal patient population from patients carrying fetuses at high risk for neonatal lung disease in antenatal examinations.

Real-Time Ultrasound Assessment of Body and Breathing Movements and Abdominal Diameter in Fetal Lambs From 55 Days of Gestation to Term

We used real-time ultrasound to measure motility and abdominal diameter in fetal lambs at weekly intervals for 30 minutes from 55 days to term (n = 8). Fetal body movement counts/min were relatively constant between 55 and ~90 days and declined progressively thereafter, a relationship best described by piecewise linear regression with 2 elements. The break point in the regression curves averaged 91.9 ± 5.2 days. The relationship between gestational age and abdominal diameter was also best described by piecewise linear regression. The break point of 113.1 ± 3.9 days was significantly greater than the movement break point. There was a significant linear relationship between the movement and abdominal break points, with the latter occurring 21.6 ± 6.6 days later. These results suggest that both fetal motility and growth may decrease in order to lower fetal O2 demands to match the progressive decline in fetal O2 delivery with advancing gestation.

ISUOG Practice Guidelines: use of Doppler ultrasonography in obstetrics

<scp>ISUOG</scp> Practice Guidelines: use of Doppler ultrasonography in obstetrics

Umbilical cord accidents

Umbilical cord accidents

Fetal sleep organization: A biological precursor of self-regulation in childhood and adolescence?

Fetal sleep states emerge during the third trimester of pregnancy and involve multiple interconnected neuronal networks. We examined whether fetal sleep characteristics predict child and adolescent self-regulation in a non-clinical sample (study group, n=25; reference group, n=48). Combined recordings of three sleep variables (fetal heart rate, body movements and rapid eye movements) were made for 2h at 36–38 weeks’ gestation. Fetuses showing synchronous change of sleep variables (i.e. within 3min) at transition from quiet into active sleep reached a higher level of effortful control, both at 8–9 and 14–15 years, than fetuses not making synchronous transitions and compared with the reference group. Results are discussed from a Developmental Origins of Behavior, Health and Disease (DOBHaD) point of view. It is concluded that studying sleep ontogeny offers the possibility to gain insight into brain maturational processes and/or environmental adaptive processes that may have long term behavioral developmental consequences.

Atypical Fetal Response to the Mother's Voice in Diabetic Compared With Overweight Pregnancies

To characterize fetal spontaneous heart rate changes and movements and auditory-elicited heart rate changes in fetuses in diabetic pregnancies compared with those in uneventful, overweight pregnancies. Spontaneous heart rate and movements and maternal voice-elicited heart rate changes were observed in 46 mother-fetal pairs (n = 14 gestational diabetic and n = 32 overweight prepregnancy) at 36 (±1) weeks gestational age. Fetal heart rate changes, body movements, and breathing movements were observed for 20 minutes while the mother was at rest. Subsequently, each fetus was presented with a 2-minute audio recording of the mother's voice using the following 6-minute procedure: 2 minutes no-voice baseline, 2 minutes voice presentation, and 2 minutes no-voice postvoice period; heart rate was recorded continuously. There were no differences in spontaneous heart rate changes, body movements, or breathing movements between the 2 groups. Fetuses in the overweight group showed an increase in the heart rate during the playing of their mother's voice, whereas fetuses in the diabetic group showed no response. Fetuses in overweight pregnancies responded to the mother's voice with an increase in the heart rate as has been reported previously in uneventful pregnancies. The lack of response to the mother's voice in fetuses in diabetic pregnancies may represent immature neural or auditory system development, an increased sensorineural threshold, and thyroid or iron deficiency.

770: Toll-like receptor gene family expression on maternal neutrophils is down-regulated in normal and preeclamptic pregnancies

are provided in table. There was no significant effect of acetaminophen on either fetal breathing or body movements when the data was expressed as number of activity episodes, total activity time, percent of activity time, or activity rate. In addition, there was no effect of acetaminophen when fetal breathing and body movements were combined into a single composite activity score. There were no differences in the proportion of fetuses demonstrating breathing or movement sufficient to achieve a normal biophysical profile score for that parameter, nor was their a difference in time required to achieve a normal score. CONCLUSION: Acetaminophen does not impact fetal breathing or body movements in humans when given at normally prescribed doses. Thus, assessment of fetal well-being using biophysical parameters should not be effected by maternal acetaminophen use.

769: Effect of acetaminophen on fetal activity

Prostaglandin compounds have been demonstrated to suppress fetal breathing and body movements in animal models, whereas prostaglandin inhibitors such as acetaminophen have been shown to stimulate both fetal activities. Although the use of prostaglandins during induction of labor has been found to decrease fetal activity in humans, minimal data exists regarding the effects of acetaminophen. The present study aimed to determine if maternal administration of acetaminophen impacts in-utero fetal activity in normal human pregnancies.

Sonographic study of the relationship between gestational diabetes mellitus and fetal activity

Objective: To evaluate the relationship between gestational diabetes mellitus (GDM) and fetal activity. Materials and methods: We prospectively studied 18 pregnant patients with GDM and 20 pregnant patients with normal glucose screening test. An ultrasound equipmentwas used to perform a 30 min transabdominal sonographic recording for each patient. Each ultrasound exam was recorded using a DVD recorder. Fetal activity was analyzed using duration and number of episodes of fetal breathing and body movements. The recordings were analyzed using a stopwatch in order to accurately evaluate each recording. The data was statistically analyzed using the parametric and non-parametric t-test. Results: The results of the study indicated that there was a significant correlation (p = 0.007) between the duration of fetal breathing movement and GDM. Fetuses of mothers suffering from GDM had a significantly longer duration of fetal breathing movements compared with fetuses of non diabetic mothers. In addition, the total duration of fetal activity (time of fetal body movements plus fetal breathing movements) was significantly higher (p = 0.005) in GDM compared with non GDM pregnancies. The difference in fetal body movements between GDM and normal pregnancies was not statistically significant. Conclusion: The results of this study support the hypothesis that GDM has a direct influence on fetal activity. The significance of this finding should be further evaluated.

Bio-magnetic signatures of fetal breathing movement

The purpose of fetal magnetoencephalography (fMEG) is to record and analyze fetal brain activity. Unavoidably, these recordings consist of a complex mixture of bio-magnetic signals from both mother and fetus. The acquired data include biological signals that are related to maternal and fetal heart function as well as fetal gross body and breathing movements. Since fetal breathing generates a significant source of bio-magnetic interference during these recordings, the goal of this study was to identify and quantify the signatures pertaining to fetal breathing movements (FBM). The fMEG signals were captured using superconducting quantum interference devices (SQUIDs) The existence of FBM was verified and recorded concurrently by an ultrasound-based video technique. This simultaneous recording is challenging since SQUIDs are extremely sensitive to magnetic signals and highly susceptible to interference from electronic equipment. For each recording, an ultrasound-FBM (UFBM) signal was extracted by tracing the displacement of the boundary defined by the fetal thorax frame by frame. The start of each FBM was identified by using the peak points of the UFBM signal. The bio-magnetic signals associated with FBM were obtained by averaging the bio-magnetic signals time locked to the FBMs. The results showed the existence of a distinctive sinusoidal signal pattern of FBM in fMEG data.