Studies on features of fetal movement and development of human fetus with use of fetal actogram

In 167 normal fetuses at 26 to 41 weeks of gestation, features of fetal movement and fetal development were investigated with use of actocardiograph in connection with a microcomputer system. The signals of fetal movement obtained by actocardiograph were stored in a floppy disc every 250 ms for 5 minutes through an AD-converter, and were analyzed every 5 minutes with the computer to reveal 3-dimensional (3-D) histograms. The 3-D histogram of fetal movement was composed of number, amplitude and interval of the signals in 11 voltage steps between 0.05 and 0.55V. The histogram clearly indicated state of fetal behavior, being either resting or active state. Fetal movement such as rolling movement, breathing movement and hiccup could be also identified with the computer analysis. In 68 normal fetuses at 14 to 41 weeks of gestation, the cross-correlation between fetal movement and fetal heart rate (FHR) were examined with the computer analysis. Finally fetal responses to acoustic and light stimulation were evaluated with use of pure-tone generator and flashlight. Acoustic stimulation was carried out in 53 normal fetuses at 28 to 41 weeks and light stimulation was performed in 116 normal fetuses at 18 to 41 weeks of gestation. The fetal responses were evaluated with actocardiogram. As a result, 1) Frequency in active state decreased and resting state increased as gestational weeks advanced, and then the frequencies of both state remained constant after 37 weeks of gestation. Duration of resting state also increased from 26 weeks to 37 weeks. These observations may suggest that fetal behavior can be established by 37 weeks of gestation. 2) Frequency in rolling movement decreased until 37 weeks of gestation, and then the movement increased during 38-41 weeks. Frequency in breathing movement increased to 33 weeks of gestation, then it remained constant. Hiccup occurred most frequently at 30-33 weeks, and it decreased thereafter. The function in fetal respiratory movement may be accomplished by 33 weeks of gestation. 3) Positive cross-correlation between fetal movement and FHR was observed as gestational weeks advanced. The correlation coefficient increased from 14 weeks up to 41 weeks. Acceleration of FHR following fetal movement eventually occurred in fetuses at 16 weeks, but the onset of acceleration delayed than normally occurred in developed fetuses. The delay was shortened in fetuses at 24 weeks and this was comparable to the delay in developed fetuses. These results suggest that the linkage of the acceleration of FHR with fetal movement is established at 24 weeks of gestation.(ABSTRACT TRUNCATED AT 400 WORDS)     

Does fetal tracheal fluid flow during fetal breathing movements change before the onset of labour?

Objective To examine changes in intra-tracheal fluid flow parameters during fetal breathing movements throughout the second half of pregnancy in the normally developing human fetus.
Design Prospective cross-sectional study.
Setting Fetal medicine unit at the Charité University Hospital in Berlin.
Methods Assessment of tracheal fluid flow was attempted in 340 healthy fetuses (GA 20–40 weeks) in which fetal breathing movements were seen by B-mode scan. Colour Doppler was applied to visualise the tracheal fluid flow, followed by spectral Doppler to record the velocity waveforms. The records of 53 fetuses divided into five gestational age groups (20–23, 24–27, 28–31, 32–35 and 36–40 weeks of gestation) containing 40 or more continuous breathing cycles (inspiration and expiration) were considered for analysis. Only regular breathing phases were examined and the volume obtained by integration of the tracheal fluid flow displaced during fetal breathing movements was calculated.
Results The intra-tracheal flow volume moved during inspiration (Vi) and expiration (Ve) increased until 36 weeks of gestation after which there was a flattening until term. This suggests either a reduction of lung liquid production or a diminished lung liquid volume. The median difference between Vi and Ve was positive in the first four age groups and negative in the last one suggesting that, in mature fetuses, the effect of fetal breathing movements no longer results in an influx.
Conclusions Our data demonstrate a modification in fetal behaviour that manifests itself during the last four weeks before birth and has the potential to reduce lung liquid volume.     

Longitudinal measurements of fetal breathing, body movements, heart rate, and heart rate accelerations and decelerations at 24 to 32 weeks of gestation

Fetal breathing, fetal body movements, fetal heart rate, and fetal heart rate accelerations and decelerations were studied longitudinally in healthy fetuses between 24 and 32 weeks' gestation in the second and third hour following an 800 kcal maternal meal. The expected increase in fetal breathing following a maternal meal was not seen until fetuses were at 30 to 32 weeks' gestation. The number of body movements decreased and the interaction between body movements and fetal heart rate accelerations became more evident as fetuses became older. Fetal heart rate decelerations increased with gestational age, and the relative proportion of total decelerations that were either associated with body movements or were part of a deceleration/acceleration/deceleration complex increased from 24 to 32 weeks' gestation. The data support the hypothesis that gestational age is an important variable to consider when interpreting biophysical measurements in the human fetus at 24 to 32 weeks' gestation. Fetal body movements may be the single most important measurement of fetal health at these gestational ages.     

Gestational age and fetal biophysical assessment

With improved neonatal care, biophysical assessment to detect fetal asphyxia is used increasingly at an earlier gestational age. We have tested five fetal biophysical variables: nonstress test, fetal breathing movements, fetal movements, fetal tone, and amniotic fluid volume 11,012 times in 5582 singleton fetuses in whom there was a normal perinatal outcome. The nonstress test and fetal breathing movements were more likely to be abnormal at 26 to 33 weeks' gestation compared with 34 to 41 weeks. The nonstress test, fetal breathing movements, fetal tone, and amniotic fluid volume were more likely to be abnormal at 42 to 44 weeks' gestation compared with 37 to 41 weeks. Fetal biophysical tests should be interpreted in relation to gestational age.     

The effect of maternal fasting on the fetal biophysical profile.

OBJECTIVES: To determine fetal biophysical profile changes in women observing Ramadan with uncomplicated singleton pregnancy. METHODS: In this cross-sectional observational study healthy women who were observing Ramadan at 30 weeks or more of gestation were recruited as well as a non-fasting control group matched for age, parity, and gestational age. Ultrasound examination included assessment of amniotic fluid volume, fetal bladder volume, fetal biophysical profile, and umbilical artery Doppler flow. RESULTS: A total of 162 pregnant women were observed. Mean umbilical artery pulsatility index, vertical amniotic pool depth, and fetal bladder volume were similar in the study and control groups. However, there was a significant difference in biophysical scores between the two groups. In the fasting group, 30 of 81 fetuses (37%) had a score of 6/8 compared with 11 of 81 fetuses (13.6%) in the control group (P=0.001). All fetuses in both groups with a biophysical score of 6/8 showed no breathing movements. CONCLUSIONS: Fetal breathing movements are reduced during maternal fasting.     

Relationship of fetal breathing movement pattern to surfactant phospholipid levels in amniotic fluid and postnatal respiratory complications

Fetal breathing patterns in 102 patients delivering before 37 weeks of gestation were divided into three types by the duration of successive respiratory activity using an ultrasonic scanner. Approximately 80% of the fetuses with fetal breathing absent or less than 9 s developed neonatal respiratory complications, including 11 cases of severe RDS and 8 cases of apnea of prematurity. However, no infant showing breathing activity of 30 s or more in utero experienced severe respiratory complications after birth. Furthermore, the surfactant phospholipid concentration in amniotic fluid was significantly increased with prolongation of successive fetal breathing activity. These results suggest that the duration of successive fetal breathing movements closely relates with fetal lung development including biochemical and neuromuscular systems in the humans, i.e. functional maturation of the fetal respiratory system, and also that prenatal analysis of breathing patterns may permit evaluation of pulmonary functional capacity after birth.     

The relationship between fetal activity and behavioral states and fetal breathing movements in normal and growth-retarded fetuses

The incidence of fetal breathing was studied during the course of behavioral state observations on 28 low-risk fetuses between 32 and 40 weeks' gestational age and on 12 growth-retarded fetuses between 36 and 40 weeks. Real-time ultrasound scanners were used to detect fetal eye, body, and breathing movements, and the fetal heart rate was recorded continuously. The mean duration of the observation sessions was 110 minutes. The mean incidence of fetal breathing was greater during periods of fetal activity (body and eye movements present, greater heart rate variability) than during quiescence (body and eye movements absent, narrowed heart rate variability) at all gestational ages studied in both low-risk and growth-retarded fetuses. During periods when one of the state variables (body movements, eye movements, heart rate pattern) was in its active condition while the other two were quiet, or the reverse, the incidence of fetal breathing was intermediate between those found when all three state variables were in agreement. After behavioral states had developed, at 38 and 40 weeks, the mean incidence of fetal breathing in the low-risk fetuses was greater during active states than during the quiet state. There was no apparent increase in the degree of linkage between fetal breathing and other expressions of fetal activity after the emergence of behavioral states.     

The rate and regularity of breathing movements in the normal and growth-retarded fetus

The rate and regularity of fetal breathing movements (FBM) were determined in 14 women with uncomplicated singleton pregnancies, eight of whom were between 30 and 33 weeks gestation and six between 37 and 40 weeks gestation. Similar observations were made in 19 women with pregnancies complicated by severe intrauterine growth retardation, 11 of whom were between 30 and 33 weeks and eight between 37 and 40 weeks. In normal pregnancy recordings of breath-to-breath intervals showed that FBM became more regular with advancing gestational age, and the rate [breaths/min, mean (SEM)] slowed from 57.2 (1.3) at 30-33 weeks to 47.9 (0.8) at 37-40 weeks. FBM in the growth-retarded group were regular at each gestation studied and the rate was even slower than in the normal group at term, being 41.9 (1.2) at 30-33 weeks and 41.1 (1.0) at 37-40 weeks. Hyperoxia and hypercapnia appeared to have no consistent effect on fetal breathing rate. Fasting for greater than 12 h considerably reduced the rate of FBM in the normal fetus but only marginally so in those with growth retardation. It is concluded that the pattern of FBM provides more information about the fetus than the amount of time spent breathing, particularly when growth is retarded.     

Fetal behaviour in growth retardation: its relationship to fetal blood flow

The fetal behaviour of asymmetrical growth retarded fetuses was compared with that of a control group of healthy fetuses. Fetuses underwent simultaneous cardiotocographic and echographic examinations for two consecutive hours at 36-38 weeks of gestation. The distribution of gross fetal body movements, fetal breathing movements and fetal eye movements was analysed during the different fetal heart rate patterns. Furthermore, the incidence and organization of fetal behavioural states was investigated. The degree of vascular peripheral resistance was also evaluated by means of pulsed doppler ultrasonic equipment. Growth retarded fetuses were divided into two groups on the basis of the presence or absence of end diastolic flow in the fetal thoracic descending aorta. Growth retarded fetuses showed a delay in the integration of behavioural patterns and a lower coincidence of behavioural states. These findings are particularly evident in the fetuses with a severe increase of peripheral vascular resistance (absence of end diastolic flow in descending aorta). Thus, we suggest that a delay in central nervous system development is present in asymmetrical growth retarded fetuses and that there is a possible relationship of this delay to the degree of peripheral vascular resistance.     

The development of fetal behavioural states: a longitudinal study

In order to evaluate the development of fetal behavioural states a longitudinal study was performed on 35 healthy fetuses during the last trimester of pregnancy. Fetal heart rate (FHR), gross fetal body movements (FM), fetal eye movements (FEM), fetal breathing movements (FBM) and micturition were simultaneously studied at two-week intervals from 28 weeks gestation onwards. Well-defined fetal behavioural states were observed only after 36 weeks gestation. Between 28 and 36 weeks the quiet-activity cycle of FHR was always detected and some fetal biophysical activities seemed to become related around this cycle.     

Infantile regressions: Disorganization and the onset of transition periods

Abstract

To evaluate the ontogenesis of ultradian rhythm of alternating eye movement (EM) and no eye movement (NEM) period durations, a cross-sectional study was conducted on 240 human fetuses from 25 to 41 weeks of gestation, using real-time ultrasound to observe eye movements. Two critical points for the duration of the EM period were found at 29-30 and 37-38 weeks of gestation, whereas for the duration of the NEM period, two critical points were again found, at 31-32 and 37-38 weeks of gestation. However, the mean duration of the EM period was constant from 25-26 to 29-30 weeks of gestation, and then increased from 29-30 to 37-38 weeks of gestation. The mean duration of the EM period was also almost constant from 25-26 to 31-32 weeks of gestation, and then increased from 31-32 to 37-38 weeks of gestation. Durations of both the EM and NEM period become stable with diminished variance after the same gestational age of 37-38 weeks. These findings could imply that two separate mechanisms exist, one for maintaining the duration of the EM period and another for maintaining the duration of the NEM period. Both switching and maintaining mechanisms responsible for ultradian rhythm of the EM and NEM periods have matured at 37-38 weeks of gestation.     

4D ultrasound study of fetal facial expressions in the third trimester of pregnancy

Objective: To evaluate the frequencies of fetal facial expressions in the third trimester of pregnancy, when fetal brain maturation and development are progressing in normal healthy fetuses.

Methods: Four-dimensional (4?D) ultrasound was used to examine the facial expressions of 111 healthy fetuses between 30 and 40?weeks of gestation. The frequencies of seven facial expressions (mouthing, yawning, smiling, tongue expulsion, scowling, sucking, and blinking) during 15-minute recordings were assessed. The fetuses were further divided into three gestational age groups (25 fetuses at 30–31?weeks, 43 at 32–35?weeks, and 43 at ≥36?weeks). Comparison of facial expressions among the three gestational age groups was performed to determine their changes with advancing gestation.

Results: Mouthing was the most frequent facial expression at 30–40?weeks of gestation, followed by blinking. Both facial expressions were significantly more frequent than the other expressions (p?p?=?.031). Other facial expressions did not change between 30 and 40?weeks. The frequency of yawning at 30–31?weeks was significantly higher than that at 36–40?weeks (p?Conclusions: Our results suggest that 4D ultrasound assessment of fetal facial expressions may be a useful modality for evaluating fetal brain maturation and development. The decreasing frequency of fetal yawning after 30?weeks of gestation may explain the emergence of distinct states of arousal.     

The rate and regularity of breathing movements in the normal and growth-retarded fetus

Summary. The rate and regularity of fetal breathing movements (FBM) were determined in 14 women with uncomplicated singleton pregnancies, eight of whom were between 30 and 33 weeks gestation and six between 37 and 40 weeks gestation. Similar observations were made in 19 women with pregnancies complicated by severe intrauterine growth retardation, 11 of whom were between 30 and 33 weeks and eight between 37 and 40 weeks. In normal pregnancy recordings of breath-to-breath intervals showed that FBM became more regular with advancing gestational age, and the rate [breaths/min, mean (SEM)] slowed from 57.2 (1.3) at 30–33 weeks to 47.9 (0.8) at 37–40 weeks. FBM in the growth-retarded group were regular at each gestation studied and the rate was even slower than in the normal group at term, being 41.9 (1.2) at 30–33 weeks and 41.1 (1.0) at 37–40 weeks. Hyperoxia and hypercapnia aeared to have no consistent effect on fetal breathing rate. Fasting for >12 h considerably reduced the rate of FBM in the normal fetus but only marginally so in those with growth retardation. It is concluded that the pattern of FBM provides more information about the fetus than the amount of time spent breathing, particularly when growth is retarded.     

Simultaneous recording of fetal breathing movements and body movements in twin pregnancy

Fetal breathing and body movements were simultaneously evaluated in twin pregnancies in order to determine to what extent these activities occur in a synchroneous pattern in both twin fetuses and if fetal position, presentation or sex have an influence on their behavior. Thirty healthy pairs of twins at 34-37 weeks of gestation were studied. Twenty-six percent of fetal body movements and 49% of breathing movements occurred simultaneously in both fetuses. The overall total simultaneous fetal activity rate was 53.3%. The length of breathing movements and total activity (summation of breathing and body movements) of the fetuses positioned on the right side of the uterus were significantly longer than in fetuses positioned on the left side of the uterus (p = 0.002) and (p less than 0.0001) respectively. This was also true for subgroups where only fetuses in the same presentation or of the same sex were compared. It is concluded that the fetus positioned on the right side of the uterus is more active and that fetal sex or presentation had no significant effect on intrauterine fetal activity in twin pregnancies.     

The relationship between movements and accelerations in fetal heart rate at twenty-four to thirty-two weeks' gestation

The purpose of this study was to establish the relationship between fetal heart rate accelerations and fetal body movements in fetuses at 24 to 32 weeks' gestation. The results suggest that body movements in younger fetuses do not occur with accelerations that are readily recognizable (i.e., less than 15 bpm), but as fetuses get older, the interaction between body movements and fetal heart rate becomes more evident and accelerations become more recognizable (i.e., greater than or equal to 15 bpm). The data presented suggest that there is a maturational aspect to the relationship between fetal heart rate and fetal body movements as fetuses increase in gestational age from 24 to 32 weeks. The conclusion, therefore, is that the nonstress test, as presently defined for older fetuses, is not valid for gestations below 32 weeks, and new criteria must be established.     

Intrauterine fetal activity in at term and prolonged pregnancies

Fetal body movements and breathing movements were recorded with a real time ultrasound scanner in 26 fetuses. There were two recording periods of 25 min each, before and half and hour after maternal IV administration of 50 gr glucose. Six fetuses were at 280 days of gestation (Group A), twelve fetuses were at 294 days of gestation (group B), eight fetuses at 294 days gestation were classified as stage I postmature (group C). The incidence of fetal body movements was not significantly different in the three groups. Maternal glucose administration had no significant influence on fetal body movements in any group. On the other hand fetal breathing activity was significantly increased in all three groups after maternal glucose administration. Breathing activity was significantly greater in group A when compared to group C in both recording periods, and when compared to group B in the period which followed maternal glucose administration. It is concluded that fetal breathing activity is reduced in prolonged pregnancies.     

Ultrasonic evaluation of fetal body movements over twenty-four hours in the human fetus at twenty-four to twenty-eight weeks' gestation

Continuous 24-hour observations of fetal gross body movements were performed in 20 women between 24 and 28 weeks of gestation by means of real-time ultrasound examination. At 24 to 26 weeks, fetuses moved 13.1% +/- 0.3% of the time, which was not significantly different from the incidence of 12.4% +/- 0.8% at 26 to 28 weeks' gestation. An examination of the number of movements per hour demonstrated that fetuses at 24 to 26 weeks' gestation moved on the average 53.4 +/- 1.6 times/hr, which was significantly different from 26 to 28 weeks' gestation when fetuses made 46.2 +/- 1.4 movements/hr. When examined on an hourly basis, fetuses in both age groups demonstrated a significant increase in the number of movements overnight from 2300 to 0800 hours. Intermovement intervals were also examined. Ninety-nine percent of intervals less than 6 minutes in both age groups contained movement. The longest observed quiescent interval was 24 minutes in both age groups. These data suggest that the incidence of fetal body movements is different than that observed in fetuses during the last 10 weeks of gestation. Fetuses at 24 to 28 weeks' gestation exhibit a diurnal pattern of fetal movement and move more frequently than do older fetuses. However, these movements are of a sporadic nature and relatively short duration. Thus these fetuses do not appear to have well-defined periods of rest and activity.     

Computerized analysis of fetal heart rate parameters by gestational age.

OBJECTIVE: The aim of this study is to define the reference ranges for fetal heart rate (FHR) parameters according to gestational age, by determining the relationship between the FHR and gestational age using a computerized FHR analysis system. METHODS: Using our own software developed by Hanyang University Hospital in Korea, non-stress tests were performed for 20 min. FHR parameters for 6455 subjects were analyzed for various gestational groups; <25 weeks, 25-28 weeks, 29-32 weeks, 33-36 weeks, 37-40 weeks, and >40 weeks. RESULTS: The FHR parameters were related to gestational age. The mean baseline FHR, signal loss, and fetal movements decreased significantly with gestation (P<0.0001). The variability and accelerations of FHR were highest for the 37-40 weeks gestational group (P<0.05). CONCLUSIONS: The results showed that overall, the differences in the FHR parameters between gestational groups were statistically significant, and the gestational age of the fetus should be considered when interpreting FHR patterns.     

胎儿肾积水的产前超声诊断及预后评估

目的 探讨胎儿肾积水的产前超声诊断的临床意义及其预后评估价值.方法 2004年12月至2005年11月在浙江大学医学院附属妇产科医院就诊的妊娠20周以上的9526例单胎孕妇行常规产前超声检查,发现胎儿肾盂前后径≥8 mm者诊断为肾积水而纳入本研究.并按Grignon分级法进行分级,定期检查和记录妊娠结局,直至分娩.结果 (1)胎儿肾积水的发生率及Grignon分级:9526例中共有162例胎儿发生肾积水,发生率为1.7%.于肾积水高峰期行Grignon分级,1级71例,2级59例,3级7例.4级3例,5级22例.(2)发生肾积水的孕周分布:初次发现胎儿肾积水的孕周平均为(33±5)周.肾积水程度达到最高峰的孕周平均为(36±3)周.110例(68%)胎儿肾积水在妊娠期即自行消失,消失孕周平均为(37±4)周.(3)不良妊娠结局:162例肾积水胎儿中有不良妊娠结局40例(25%),其中11例初次发现于孕20～24周中有3例(27%),20例初次发现于孕25～28周中有6例(24%),53例初次发现于孕29～32周中有14例(26%),48例初次发现于孕33～36周中有11例(23%),30例初次发现于孕37～40周中有6例(20%).胎儿肾积水Grignon分级越高,不良妊娠结局发生率也越高,3级及以上者不良妊娠结局发生率达100%.(4)随访结果 :分娩健康新生儿122例(75%,122/162),为110例出生前肾积水自行消失者和12例出生后1周内肾积水自行消失者,随访2年以上其生长发育正常,无泌尿系统后遗症;分娩肾积水新生儿20例(12%,20/162),为出生后1周内超声复查仍存在肾积水者,其中Grignon分级在3级及以下者11例,肾积水消失时间在出生后3个月至12个月不等,患儿生长发育均与同龄儿无明显差异,无泌尿系统症状.结论 胎儿肾积水初次发现的孕周越早,程度越严重,胎儿预后越差.应用Grignon分级法对胎儿肾积水程度进行分级可用于评估肾积水胎儿的预后,以指导临床处理.     

Estados de comportamiento intraútero en los hijos de madres con diabetes tipo 1

ObjectiveTo establish to possible existence of differences in fetal neurological devolopment through analysis of the characteristics of fetal behavioral states in diabetic pregnanciesMaterial and methodWe compared the results obtained in a control group, composed by 15 pregnant women with physiological pregnancy and another group composed by 15 pregnant women with type 1 diabetes. Gestacional age at the time of study was ≥ 37 and ≤ 41 weeks. Ocular activity, body movements and patterns of fetal cardiac frequency were sumultaneously recorder for 1 h using ultrasonography and kinetocardiography. The time spent by the fetuses in behavioral or coincident states, the ability to establish stable behavioral states and the number of changes in state (behavioral stability) were evaluatedResultsThe time spent by the fetuses in a state of deep sleep (F1) was significantly lower in the fetuses of diabetic women at 38 weeks' gestation. The duration of periods of behavioral incoordination (F5) was, in contrast, higner in this group and differences between groups were statustucally significant at 36-37 weeks. The number of changes in state was higher in the fetuses of diabetic women than in controlsConclusionsType 1 diabetes is associated with a lower ability to establish stable behavioral states in the fetuses of fiabetic mothers