Le bâillement, du réflexe à la pathologie
Le bâillement : de l'éthologie à la médecine clinique
Le bâillement : phylogenèse, éthologie, nosogénie
 Le bâillement : un comportement universel
La parakinésie brachiale oscitante
Yawning: its cycle, its role
Warum gähnen wir ?
Fetal yawning assessed by 3D and 4D sonography
Le bâillement foetal
Le bâillement, du réflexe à la pathologie
Le bâillement : de l'éthologie à la médecine clinique
Le bâillement : phylogenèse, éthologie, nosogénie
 Le bâillement : un comportement universel
La parakinésie brachiale oscitante
Yawning: its cycle, its role
Warum gähnen wir ?
Fetal yawning assessed by 3D and 4D sonography
Le bâillement foetal

mystery of yawning 

mise à jour du
30 juillet 2006
Int J Gynaecol Obstet
Four-dimensional sonographic assessment
of fetal facial expression early
in the third trimester
Yan F, Dai SY, Akther N, Kuno A, Yanagihara T, Hata T.
Department of Perinatology and Gynecology, Kagawa
University School of Medicine, Miki, Kagawa, Japan


Tous les articles consacrés au bâillement foetal
Fetal yawning: all publications
Bâillements du foetus: la naissance d'un comportement
révèlée par l'échographie 4D
Video de bâillement foetal à 23 semaines en Echo 4D
Video de bâillement foetal à 13 semaines en Echo 4D
Sonography Edited by: Kerry Thoirs
Fetal Yawning Olivier Walusinski
Chapter 18 Pages 325-332
Piontelli A. Fetal Yawning in Development of Normal Fetal Movements. The fisrt 25 weeks of gestation. Spinger. 2010. 135p.
OBJECTIVE: To evaluate the characteristic patterns of facial expression in fetuses aged from 28 to 34 weeks using 4-dimensional (4-D) ultrasonography.
METHODS: The faces of 10 healthy fetuses aged from 28 to 34 weeks were recorded continuously for 15 min with a 4-D ultrasonographic machine performing up to 25 frames per second. The occurrence rates of blinking, mouthing, yawning, tongue expulsion, smiling, scowling, and sucking were evaluated.
RESULTS: Mouthing was the most frequent facial expression (median, 6.5; range, 2-19) whereas the least frequent were scowling (median, 1; range, 0-9) and sucking (median, 1; range, 0-2). Mouthing was evident in all fetuses and significantly more frequent than any other movement (P<.05). Yawning (median, 3; range, 0-6), smiling (median, 2; range, 0-9), and blinking (median, 1.5; range, 0-6) were observed in most cases. Tongue expulsion (median, 1.5; range, 0-5), scowling, and sucking were each observed in 6 cases.
CONCLUSION: 4-D sonography provides a means of evaluating fetal facial expression early in the third trimester. It may be a key to predicting fetal brain function and well-being and an important modality in future fetal neurophysiologic research
fetal yawning
Fetal neurobehavioral patterns have been considered indicators of nervous system development. Many studies have shown that normally developing fetuses and fetuses at risk had different patterns of behavior. For example, anencephalic fetuses have been found to have fewer hand and body movements and hydrocephalic fetuses to have fewer eye movements.
Fetal facial movements, controlled by the nuclei of facial nerves in the brain, have been investigated using 2-dimensional (2-D) ultrasonography. However, it is difficult to evaluate complex facial activity because of the anatomic features of the face and the limitations of this technique.
Only with the appearance of 4-dimensional (4-D) ultrasonography have a full range of facial expressions, such as scowling, crying, and smiling, been observed. To determine whether there was a fetal facial movement pattern early in the third trimester, the present study used 4-D sonography to observe 10 healthy fetuses aged from 28 to 34 weeks.
Fetal behavior, defined as any observable action or reaction to an external stimulus by the fetus, reflects the activity of the fetal central nervous system. Insight in fetal behavior is crucial for the understanding of normal fetal well-being and in determining whether a fetus may be compromised. Moreover, a recent investigation has shown that there is behavioral continuity from fetal to neonatal life, which probably includes facial expression .
The observation of fetal facial expression may be of diagnostic value in prenatal medicine. According to previous studies, general fetal movements can be observed as early as the 8th week As pregnancy advances, the incidence of general movements tends to decrease and the incidence of mouthing tends to increase . At the 34th week, the fetus begins to display some degree of motor coordination. A link between fetal eye movements, body movements, and heart rate pattern, which can be observed from the 25th week on, becomes stable near term .
Regular mouthing and nonrapid eye movement (state 1) appear at about the same time, from 35 weeks on . The different phases of behavior are thought to reflect different levels of brain activity, as fetal habituation may implicate the function of the cortices . Nonrapid eye movement sleep may be an indication thalamocortical pathway function.
Blinking frequency and cognitive state are related . Also, studies have shown that abnormal fetuses exhibit different behavior patterns . With the dev lopment of ultrasonographic techniques, a great deal of progress has been made in the evaluation of the fetal face and behavior and 4-D ultrasonography has considerable advantages over 2-D and 3-D ultrasonography in this field of study.
Kurjak and colleagues used 4-D ultrasonography to study 10 healthy fetuses aged from 30 to 33 weeks, and found that eyelid and mouthing dominated at this gestational age . These investigators also confirmed that there was a behavioral continuity from prenatal to postnatal life by studying 10 fetuses aged 33 to 35 weeks , and they concluded that different facial expressions and movements might represent fetal awareness .
In the latest study by this team, 100 women with normal singleton pregnancies were recruited for longitudinal 4-D ultrasonographic examin tion to evaluate fetal neurodevelopmental parameters from the 7th to the 40th week . All types of facial expression were noted to display a peak frequency at the end of the second trimester, except for isolated eye blinking, whose frequency increases at the beginning of the 24th week.
A tendency towards decreasing frequency of facial expressions with increasing gestational age needs to be demonstrated. In the present study, a full range of fetal facial expressions early in the third trimester (from 28 to 34 gestational weeks) were investigated using 4-D ultrasonographic techniques. As in previous reports , mouthing was found to be the most active facial expression during this gestational period. However, the frequency of blinking, which in other studies was thought to be similar to that of mouthing, was lower in this study. Differences in the characteristics of the samples recruited and differences in interpreting the definition of each facial expression may be reasons for the different results.
In addition, although the same 15-min period of observation was used in the present and other studies, the limitations of such a short period have been pointed out in the latest investigation . Extending observation time and recruiting large sample sizes is needed in future studies. Although 4 D sonography could be useful in the study of fetal behavior, its disadvantages cannot be overlooked.
Several movement patterns, such as bending sideways, hiccup, and very subtle facial movements, cannot be observed, especially early in pregnancy . Moreover, as pointed out by Kurjak and colleagues, only the quantity, and not the quality, of facial movements can be studied in fetuses, because criteria for quality have not yet been determined . Presently, studying fetal behavior is very time consuming and therefore limited to research. An easier way of analyzing fetal behavior should be developed for diagnostic and prognostic use.