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H F Prechtl

Publications and source records attributed to H F Prechtl.

At least 19 recordsLinked to original sources

The relationship between the quantity and quality of prenatal movements in pregnancies complicated by intra-uterine growth retardation and premature rupture of the membranes.

In 17 fetuses with intrauterine growth retardation (IUGR), we studied the quantity of general movements and fetal breathing movements both cross-sectionally and longitudinally. In IUGR fetuses, cross-sectional comparisons were made between the quantity of fetal movements and (1) the fetal clinical condition and (2) the quality of general movements. In addition, the quantity of fetal movements in IUGR was compared with that in uncomplicated pregnancies and in pregnancies complicated by premature rupture of the amniotic membranes. In IUGR, the quantity of general movements declined from 25 weeks gestation onwards, whereas the quantity of fetal breathing movements increased. Longitudinal assessment of these parameters was obtained in four cases and showed a decline of general movements. No relationship between prenatal longitudinal data and neonatal outcome could be observed. Relating the quantity of general movements and breathing movements to the fetal condition, growth retarded fetuses were divided into three groups according to fetal deterioration. 1. Normal amount of amniotic fluid and normal fetal heart rate patterns. 2. Reduced amount of amniotic fluid. 3. Abnormal fetal heart rate patterns. The quantity of general movements as well as that of breathing movements was low in group 3, compared to group 1. In group 2 only the quantity of breathing movements and not of general movements was low. A similar pattern was found in the relation with the quality of general movements observed during fetal deterioration. Cross-sectional analysis of median values (28-31 weeks gestation) did not reveal differences in the quantity of general movements when IUGR, normal pregnancies and premature rupture of the membranes (with or without oligohydramnios) were compared. The quantity of fetal breathing movements was significantly lower in pregnancies complicated by IUGR and by premature rupture of the membranes with oligohydramnios compared to those of normal pregnancies and premature rupture of the membranes without oligohydramnios. In uncomplicated IUGR, the quantity of general movements and breathing movements is in the same range as in normal uncomplicated pregnancies. Similar to the quality of general movements, the quantitative variables were related to the fetal condition. However, in contrast to the quality of general movements, the quantity of general movements and breathing movements showed a high inter- and intraindividual variation. Therefore, the results of this study discourage the use of quantitative aspects of general movements and breathing movements as reliable indicators of the neurological condition in the individual fetus.

Cross-Sectional Studies

The effect of intrauterine growth retardation on the quality of general movements in the human fetus.

The effect of severe intrauterine growth retardation on the quality of general movements was studied longitudinally in 17 human fetuses. During the prenatal and postnatal periods, fetal movements were recorded by means of weekly 1 h ultrasound and video registrations. Neurological examinations were performed at 1, 3, 6 and 12 months after birth. No clear effect of uncomplicated intrauterine growth retardation could be detected on the quality of general movements. General movements became slow and small in amplitude (4/5) in cases where there was a reduction in the amount of amniotic fluid. Parallel to the onset of abnormal fetal heart rate patterns, general movements became poor in repertoire (7/7), while they were hardly discernible after further deterioration of the fetal condition (5/7). With the exception of 3 infants with cerebral haemorrhages, the quality of general movements observed just before and after birth was identical (13/16). In these infants, the quality of general movements as well as the results of the standardized neurological examination tended to normalize at 3 months and 1 year, respectively. Uncomplicated IUGR had no marked effect on the quality of general movements or on the results of the neurological examination at the age of 1 year.

Aging

Fetal breathing movements are not a good indicator of lung development after premature rupture of membranes and oligohydramnios--a preliminary study.

The effect of severe oligohydramnios (due to prolonged premature rupture of the membranes (PROM)) on breathing movements and lung development was studied longitudinally in 11 human fetuses. Prenatally, fetal breathing movements (FBM) were scored off-line from weekly, 1 h during ultrasound recordings (n = 47). In each recording, the incidence of FBM was scored according to 4 different methods. Postnatally, the cases were retrospectively assigned to a group with normal (n = 4), partially hypoplastic (n = 3), or hypoplastic (n = 4) lungs. Compared to control fetuses, the percentage of time spent breathing (%FBM) was low (2-5%) and did not increase with gestational age. Large inter-individual and intra-individual variations in the %FBM were found in all 3 diagnostic groups. Evaluation of the %FBM according to the 4 different methods revealed no significant differences between the 3 groups. We conclude that lung development is, at least partly, independent of the incidence of FBM. Furthermore, the analysis of FBM cannot reliably predict lung development in fetuses with oligohydramnios due to PROM.

Cross-Sectional Studies

Studies on developmental neurology in the human fetus.

The development of the motor component of the embryonic and fetal central nervous system can be studied by observation of fetal movements, using real-time ultrasound. In this paper data on emergence and development of fetal movement patterns and behavioural states are reviewed in the light of the normal development of the nervous system, identification of disturbances in normal development and testing behavioural teratogenicity in the human.

Embryonic and Fetal Development

Effects of prone and supine position on heart rate, respiratory rate and motor activity in fullterm newborn infants.

Polygraphic recordings were obtained for 24 normal full-term neonates on their 4th or 5th day of life. Thirteen of the infants were first fed, laid supine for 3 hours, fed again around noon and laid prone for 3 more hours. The other 11 were first laid prone and then supine. The awake state was observed more in the supine than the prone position (P less than 0.001). Wakefulness occurred at the expense of state 1 and/or state 2. The heart rate (HR) was higher in babies lying prone. It was also higher in the afternoon than in the morning. No such relationship was found for the respiratory rate (RR). There was higher average EMG activity during state 1 in the prone position. The cross-correlation between HR and EMG activity was positive during state 2, and states 4 and 5, regardless of the position. The cross-correlation between the RR and the EMG was usually negative in state 2, and in states 4 and 5, there being many exceptions. The cross-correlation between breathing and heart-beat was mostly negative during state 2, but it eventually became positive due to periodic breathing, central apnoeas with bradycardia, stretches, and crawling movements.

Electrocardiography

Preterm and early postterm motor behaviour in low-risk premature infants.

The development of spontaneous motility and posture was studied longitudinally in 14 carefully selected low-risk preterm infants. The aim of this investigation was to provide a set of data suitable for comparison with fetuses and with neurologically abnormal preterm infants. The infants were videorecorded weekly, for one hour in a supine position, from birth until their discharge from the hospital. Ten of them were thereafter also observed at home at 3-week intervals from 3 to 18 weeks of corrected age, together with 10 healthy fullterm infants. Occurrence and duration of motor patterns and postures in periods of rest and activity were obtained by off-line analysis of the videotapes. Few significant changes were found from birth until term age in the composition and quantity of the spontaneous movement patterns. Only twitches and stretches during activity periods showed a small decline approaching term age. However, notable inter-individual differences and intra-individual fluctuations from week to week were observed. Postterm development of preterm infants was similar to that of the fullterms. Both showed considerable changes in the qualities of general movements after the first postterm weeks. Only fidgety character movements occur earlier in preterm infants. No age-specific preference postures of the limbs were found in the preterm period. Midline position of the head in supine was observed at about the same postterm age in preterm and fullterm groups. Asymmetrical tonic neck postures were very inconsistently present before term age and rapidly disappeared after term, earlier so in preterm infants.

Activity Cycles

Qualitative changes of general movements in preterm infants with brain lesions.

The aims of the study were (1) to replicate previous quantitative studies of motor activity in low-risk and high-risk preterm infants and (2) to apply a new method of systematic analysis of the qualitative characteristics of general movements in these two groups of infants. Sequential one-hour videorecordings of the unstimulated infants in the incubator were made during the preterm period and then continued during the postterm period until about 20 weeks. The high-risk group consisted only of infants with signs of haemorrhage and/or leucomalacia in the repeated ultrasonograms of the brain. The neurological follow-up continued up to a minimum of one and a maximum of three years of corrected age. The quantification of the various motor patterns in 12 matched pairs of low-risk and high-risk preterm infants revealed a slight but significant (P = 0.05) excess of isolated arm movements in the low-risk cases during the activity phase. No other movement pattern differed significantly. The qualitative assessment of general movements during the preterm period resulted in all but one of the 14 low-risk cases having a normal quality of general movements. In the lesion-group (N = 29) all the infants had an abnormal quality during the preterm period. Eight cases later became neurologically normal although 1 of them had strabism. In addition, one infant was blind (ROP) and retarded and one other had mental retardation. Nineteen infants later developed cerebral palsy (two monoplegia of a leg, three hemiplegia, 5 diplegia and 9 quadriplegia). Strabism was present in 48.3% of the whole group of 29 cases. A semi-quantitative estimation of various aspects of the abnormal general movements made a typology of abnormal patterns possible. A graphic display of developmental trajectories of individual cases, depicting the course of abnormal aspects along the time axis, helps document the evolution of abnormal signs. Their course is a better predictor of the neurological outcome than the nature and localization of the lesion, detected by imaging techniques. The qualitative assessment of general movements from videorecordings is a reliable, quick, cheap and totally non-intrusive method in neonatology for the early detection of functional impairment of the nervous system.

Brain Diseases

Does reduction of amniotic fluid affect fetal movements?

The effect of the amount of amniotic fluid on the form of fetal general movements was studied longitudinally in 19 pregnancies complicated by premature rupture of the amniotic membranes (PROM). Before birth, general movements were studied weekly by means of 1-h ultrasound observations, performed under standardized conditions. In the early postnatal period, 11 of these infants were followed with video recordings of their spontaneous movements. In the fetus, speed and amplitude of general movements were directly related to the reduction in amniotic fluid. A moderate reduction of amniotic fluid was associated with a decrease in amplitude, while a more severe reduction of amniotic fluid caused a decrease in speed as well. Postnatally, the small amplitude and low speed showed a marked tendency to normalize between 1 and 5 weeks. These results are important for the qualitative assessment of motor behaviour in pregnancies with obstetrical complications that are associated with oligohydramnios (such as PROM or intra-uterine growth retardation).

Amniotic Fluid

Body and breathing movements in near-term fetuses and newborn infants of type-1 diabetic women.

The generation of body and breathing movements was studied in relation to behavioural states in near-term fetuses (n = 12) and newborn infants (n = 7) of women with well-controlled type-1 diabetes. Results obtained from low-risk fetuses (n = 12) and neonates (n = 14) were used for comparison. Before birth, 2-h recordings were made of fetal heart rate and of fetal body movements, breathing and eye movements; the neonates were studied polygraphically during 6 h for heart rate, body movements, respiration, eye movements and EEG-pattern. The generation of body movements was similar in the fetuses of the diabetic and control groups. After birth, the duration per burst was longer in the diabetic group, both in state 1 and state 2, resulting in increased incidences. The incidence of fetal breathing movements tended to be higher in the diabetic group, but differences with the control group did not reach statistical significance. Breathing rate was considerably slower in fetuses of diabetic women than in control fetuses, both in C1F (P less than 0.001) and C2F (P less than 0.002). This indicates altered regulation of breathing movements in diabetic pregnancy. In the neonates, breathing rate was identical in both groups. In either group breathing was slower in state 1 than in state 2; such a difference was not present before birth. Periodic breathing occurred more often in the infants of diabetic women, especially in state 2 (P less than 0.02). Behavioural state organization was poor in the diabetic group, both before and after birth and resembled that of more immature fetuses and infants. The continuity of the poor behavioural state regulation from prenatal into postnatal life indicates that this cannot be attributed to the instantaneous unfavourable condition before birth.

Female

Fetal behaviour.

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Female

Posture and spontaneous motility in fullterm infants.

Posture and spontaneous motor patterns during the first days of life were studied in ten healthy fullterm infants by direct observation and videorecording. The aim of the study was to provide a description of motor and postural characteristics of normal newborns. The infants were recorded for 1 h on their first and fourth day of life, when unstimulated in an incubator. Incidence and duration of the different body postures and motor patterns were scored during the replay of the videorecordings. The preference for the fully flexed posture of arms and legs described in the literature could not be confirmed. There was a large intra- and inter-individual variability in the postural repertoire. No particular posture, characteristic for each behavioural state, existed. Similar postures rarely occurred in the same infant on the first and fourth day. Extended postures more often occurred on the fourth day. Spontaneous motility consisted of several distinct movement patterns, the occurrence of which in states 1 and 2 was computed for day 1 and day 4. Motor patterns were differently related to the states. No differences were noted in the motor activity between the first and fourth days. Large inter-individual differences, but an intra-individual consistency, were found in the rates of specific motor patterns: infants who showed a low or high rate of particular movements on day 1 maintained the same characteristic on day 4. There was no overall low or high motor activity.

Female

Vibro-acoustic stimulation of the human fetus: effect on behavioural state organization.

Vibro-acoustic stimulation of the human fetus in being increasingly performed both antenatally and during labour, to differentiate between poor and good fetal health in cases of flat or otherwise suspect fetal heart rate patterns. In a controlled study we investigated the effect of the electronic artificial larynx (EAL) on fetal behavioural state organization. In 10 healthy women with normal pregnancies of 38-40 weeks of gestation, recordings of fetal heart rate, body movements and eye movements, with a duration of 120-210 min, were carried out during two consecutive days. In each fetus, 3-4 episodes of state 1F and consecutive state 2F were studied, one of which served as a control observation. EAL stimulation during state 1F was associated with excessive fetal movements and with a state change in 7 out of 9 observations (four times into 2F; three times into 4F). Stimulation during state 2F was associated with a change into 4F in four of the nine observations. On days with EAL stimulation the fetuses spent more time in state 4F or in an episode not classifiable (because of an atypical FHR pattern with tachycardia and small accelerations) than control fetuses (21% vs. 3% of time). Disorganized states or periods of state 4F sometimes lasted for more than 1 h following the stimulation. It is concluded that stimulation with the EAL induces excessive fetal movements, a prolonged tachycardia, non-physiological state changes and a disorganisation and change in the distribution of fetal behavioural states. Until more is known regarding the safety and risks of vibro-acoustic stimulation, it should not be used in a routine clinical setting.

Acoustic Stimulation

The effect of (induced) maternal emotions on fetal behaviour: a controlled study.

In ten healthy near-term pregnant women the effect of induced maternal emotions on fetal motor behaviour was studied. Emotions were induced by showing a film of a normal delivery. Fetal behaviour was recorded by means of real-time ultrasound observations of general movements and eye movements and by fetal heart rate monitoring. The observations had a duration of 2 h. The data were compared with those obtained during a 2-h control period, which took place the day before (n = 5) or after the study period (n = 5). Maternal emotions (induced) were measured by means of psychological tests. No effects on fetal motor activity or on behavioural state organization could be found as a result of this film. There was, however, a significant positive correlation (P less than 0.01) between the mean level of anxiety of the women and the motor activity of the fetuses.

Adult

The emergence of fetal behaviour. III. Individual differences and consistencies.

Intra- and inter-fetal consistencies and differences in motor activity were studied in 12 healthy nulliparous women during the first half of gestation. Real-time ultrasound observations, lasting 60 min, were performed weekly from 7 to 15 weeks of gestation and at 17 and 19 weeks. The various types of movements were categorized according to a previously developed classification system. Data on general movements during the second half of gestation were carried out on the same group of women and these results are also included in this study. Intra-individually there appeared to be a relative week-to-week consistency in the amount of total motor activity, i.e. the sum of all the movement patterns. There was a slight tendency of intra-fetal consistency when the incidence of general movements during the first half of gestation was compared to that during the second half. The other movement patterns did not show these consistencies, namely, each fetus showed large fluctuations in the week-to-week incidences. Inter-individually there were large differences in the amount of the different types of movements at the various ages, which resulted in wide ranges. The sum of the rank orders which for total activity and general movements, were found weekly, were compared to those which could be expected to occur in a homogeneous population. Two fetuses appeared to be significantly different from the others on mathematical grounds. One consistently showed a high and one a low motor output. Week-to-week stability in the rank orders of the various movement patterns was studied by adding up a sum score of all the weekly changes in ranks. Three fetuses were found to be stable and three showed large fluctuations. The others were in between these extremes. The ranks of the movements from high to low frequency, appeared to be strictly age dependent, whereby all the fetuses followed the same developmental trend. There were no differences between female and male fetuses in any of the movement patterns.

Embryonic and Fetal Development

Developmental neurology of the fetus.

The use of modern ultrasound equipment has opened the way to fetal neurology. The aim is to provide the obstetrician with standardized and comprehensive methods to evaluate the neurological condition in compromised fetuses. Such possibilities will greatly improve assessments which have so far been based only on fetal heart rate monitoring and quantitative counts of fetal motility. The most important candidates for neurological assessment are the quality of fetal movements, in particular of general movements, and in the near-term fetus the organization of behavioural states. Less suitable, because of limited sensitivity, is the quantitative assessment of fetal movements, even when carried out with ultrasound. The most problematic approach is testing the fetus with vibro-acoustic stimuli, which induce abnormal behavioural states of prolonged duration and are therefore potentially harmful.

Central Nervous System

The blood flow velocity waveform in the fetal internal carotid and umbilical artery; its relation to fetal behavioural states in the growth retarded fetus at 37-38 weeks gestation.

In eight women whose fetuses showed evidence of intrauterine growth retardation (IUGR), the relation was examined between the blood flow velocity waveform in the fetal internal carotid and umbilical artery and fetal behavioural states at 37-38 weeks gestation. In both vessels there was a virtual overlap of pulsatility index values originating from state 1F and 2F, reflecting behavioural state independency. In the internal carotid artery this state independency is associated with moderately reduced pulsatility index values.

Blood Flow Velocity