Ultrasonic Assessment of Fetal Activity

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.

Reduced fetal movements: the case of Fetomaternal Hemorrhage. Case series and proposal of a management protocol

Fetomaternal hemorrhage (FMH) was reported more than 60 years ago for the first time defined by the transfer or transfusion of fetal blood into the maternal circulation before or during delivery. The transfused volume is usually very small but when this value exceeds, it may be clinically significant. Antenatal diagnosis of severe FMH is difficult and it can be suspected in case of reduction of fetal movements, abnormal cardiotocography and ultrasound. FMH is associated to different adverse outcomes and admission to neonatal intensive care. The low incidence of FMH limits the studies, thus being able to rely only on diagnosis and retrospective studies. We present case series of FMH and analyze the steps with the purpose of defining a flow-chart for early diagnosis and management of FMH.

Impact of Covid-19 on attendances for a 1st episode of reduced fetal movements: A retrospective observational study

Background

Prior studies have demonstrated an increased stillbirth rate. It was suggested that the COVID-19 pandemic may have impacted on attendances for reduced fetal movements. Thus, we sought to ascertain the impact of the pandemic on attendances for reduced fetal movements (RFM) in our unit, ultrasound provision for reduced fetal movements, and the stillbirth rate.

Methods

This was a single site retrospective cohort study involving all women complaining of a 1^st episode of reduced fetal movements between 01/03/2020-30/04/2020 (COVID) to 01/03/2019-30/04/2019 (Pre-COVID). Data were retrieved from computerised hospital records and statistical analyses were performed using GraphPad Prism and SPSS.

Results

22% (179/810) of women presented with a 1^st episode of reduced fetal movements Pre-COVID compared to 18% (145/803) during COVID (p = 0.047). Primiparous women were significantly over-represented in this population with a 1.4-fold increase in attendances during COVID (67% vs 48%, p = 0.0005). Neither the total stillbirth rate nor the stillbirth rate amongst women who presented with reduced fetal movements changed during COVID. Ultrasound provision was not impacted by COVID with 95% of the scans performed according to local guidelines, compared to Pre-COVID (74%, p = 0.0001).

Conclusions

There is a significant decrease in 1^st attendances for reduced fetal movements during COVID-19 pandemic. Primiparous women were 1.4 times more likely to attend with RFM. Women should be reassured that COVID-19 has not resulted in a decreased provision of care for RFM, and has not impacted on the stillbirth rate.

Midwives' experiences of using the Mindfetalness method when talking with pregnant women about fetal movements

BACKGROUND

Information given to pregnant women about fetal movements is important in maternity care and decreased fetal movements is associated with fetal growth restriction and stillbirth. The fetal movement pattern is different for every fetus and women perceive different types of movements. Mindfetalness is a self-assessment method for a woman to use to become familiar with her unborn baby's fetal movement pattern.

AIM

We aimed to explore midwives' perceptions about informing pregnant women about fetal movements and their experiences of working with Mindfetalness in their daily work.

METHODS

A web-questionnaire was distributed to midwives who participated in a randomized controlled trial evaluating Mindfetalness, a method for the observation of fetal movements. In total, 67 maternity clinics in Stockholm, Sweden, were randomized to Mindfetalness or routine care. Of the 144 midwives working in maternity clinics randomized to Mindfetalness, 80% answered the questionnaire.

FINDINGS

The midwives thought that the leaflet about Mindfetalness was supportive in their work when informing women about fetal movements and the majority wanted to continue to distribute the leaflet when the trial ended. The midwives also expressed that the study increased their own knowledge about fetal movements. Women embraced the information about Mindfetalness positively and appreciated the written material. The midwives thought that talking about fetal movements in maternity care is an important but challenging task.

CONCLUSION

Mindfetalness is a useful tool to use in maternity clinics when informing pregnant women about fetal movements. The written information was appreciated by both pregnant women and midwives.

Ultrasound assessment of fetal hearing response to vibroacoustic stimulation

Background: Assessment of fetal responses to external stimuli could be a vital clue for understanding development of fetal neurophysiology, which is extremely challenging to explore. To study hearing development in growing human fetus, we assessed sonographic fetal movement responses to external auditory stimulus at increasing period of gestation.Method: In 123 normal pregnant women between 16 and 40 weeks' gestation, sonographic assessment of fetal movements (gross body movement, isolated limb movement, breathing movement and startle response) was carried out before and after administering vibroacoustic stimulation (VAS). Types and number of fetal movements during 5-min period each - immediately before and after application of VAS - were compared.Results: With increasing gestational age, spontaneous gross body movement decreased significantly between 16-28 and 29-40 weeks of gestation (93.3 versus 66.6%; p < .001). However, VAS significantly increased gross body movement at 29-40 weeks of gestation (66.6 versus 93.6%; p < .001). Incidence of isolated limb movement was inversely related to increasing gestational age. However, VAS was associated with significantly increase in isolated limb movement during 29-40 weeks' gestation (57.1 versus 80.9%; p = .007). VAS induced almost similar pattern of response for both fetal startle and breathing movements.Conclusions: Fetal movement responses to VAS are consistent after 28 weeks' gestation. These findings suggest fetal hearing develops at or before 28 weeks of intrauterine life.

Maternal perception of fetal movements in the third trimester: A qualitative description

PROBLEM

Decreased fetal movements is a common reason for unscheduled antenatal assessment and is associated with adverse pregnancy outcome.

BACKGROUND

Fetal movement counting has not been proven to reduce stillbirths in high-quality studies.

AIMS

The aim was to explore a qualitative account of fetal movements in the third trimester as perceived by pregnant women themselves.

METHODS

Using qualitative descriptive methodology, interviews were conducted with 19 women experiencing an uncomplicated first pregnancy, at two timepoints in their third trimester. Interview transcripts were later analysed using qualitative content analysis.

FINDINGS

Pregnant women described a sustained increase in strength, frequency and variation in types of fetal movements from quickening until 28-32 weeks. Patterns of fetal movement were consistently described as involving increased movement later in the day and as having an inverse relationship to the women's own activity and rest. At term, the most notable feature was increased strength. Kicking and jolting movements decreased whilst pushing and rolling movements increased.

DISCUSSION

Maternal descriptions of fetal activity in this study were consistent with other qualitative studies and with ultrasound studies of fetal development.

CONCLUSION

Pregnant women observe a complex range of fetal movement patterns, actions and responses that are likely to be consistent with normal development. Maternal perception of a qualitative change in fetal movements may be clinically important and should take precedence over any numeric definition of decreased fetal movement. Midwives may inform women that it is normal to perceive more fetal movement in the evening and increasingly strong movements as pregnancy advances.

Impact of maternal physical activity on fetal breathing and body movement--A review

Fetal movements, which include body and breathing movement, are important indicators of fetal well-being and nervous system development. These have been shown to be affected by intrauterine conditions. While maternal physical activity does induce a change in intrauterine conditions and physiology, its impact on fetal movements is still unclear. This paper will provide a brief review of the literature and outline the current knowledge with regards to the effects of maternal exercise on fetal body and breathing movements.

Neuron-based heredity and human evolution

It is widely recognized that human evolution has been driven by two systems of heredity: one DNA-based and the other based on the transmission of behaviorally acquired information via nervous system functions. The genetic system is ancient, going back to the appearance of life on Earth. It is responsible for the evolutionary processes described by Darwin. By comparison, the nervous system is relatively newly minted and in its highest form, responsible for ideation and mind-to-mind transmission of information. Here the informational capabilities and functions of the two systems are compared. While employing quite different mechanisms for encoding, storing and transmission of information, both systems perform these generic hereditary functions. Three additional features of neuron-based heredity in humans are identified: the ability to transfer hereditary information to other members of their population, not just progeny; a selection process for the information being transferred; and a profoundly shorter time span for creation and dissemination of survival-enhancing information in a population. The mechanisms underlying neuron-based heredity involve hippocampal neurogenesis and memory and learning processes modifying and creating new neural assemblages changing brain structure and functions. A fundamental process in rewiring brain circuitry is through increased neural activity (use) strengthening and increasing the number of synaptic connections. Decreased activity in circuitry (disuse) leads to loss of synapses. Use and disuse modifying an organ to bring about new modes of living, habits and functions are processes in line with Neolamarckian concepts of evolution (Packard, 1901). Evidence is presented of bipartite evolutionary processes-Darwinian and Neolamarckian-driving human descent from a common ancestor shared with the great apes.

Fetal response to maternal hunger and satiation - novel finding from a qualitative descriptive study of maternal perception of fetal movements

Background

Maternal perception of decreased fetal movements is a specific indicator of fetal compromise, notably in the context of poor fetal growth. There is currently no agreed numerical definition of decreased fetal movements, with the subjective perception of a decrease on the part of the mother being the most significant definition clinically. Both qualitative and quantitative aspects of fetal activity may be important in identifying the compromised fetus. Yet, how pregnant women perceive and describe fetal activity is under-investigated by qualitative means. The aim of this study was to explore normal fetal activity, through first-hand descriptive accounts by pregnant women.

Methods

Using qualitative descriptive methodology, interviews were conducted with 19 low-risk women experiencing their first pregnancy, at two timepoints in their third trimester. Interview transcripts were later analysed using qualitative content analysis and patterns of fetal activity identified were then considered along-side the characteristics of the women and their birth outcomes.

Results

This paper focuses on a novel finding; the description by pregnant women of fetal behaviour indicative of hunger and satiation. Full findings will be presented in later papers. Most participants (74% 14 of 19) indicated mealtimes were a time of increased fetal activity. Eight participants provided detailed descriptions of increased activity around meals, with seven (37% 7 of 19) of these specifying increased fetal activity prior to meals or in the context of their own hunger. These movements were interpreted as a fetal demand for food often prompting the mother to eat. Interestingly, the women who described increased fetal activity in the context of hunger subsequently gave birth to smaller infants (mean difference 364 gm) than those who did not describe a fetal response to hunger.

Conclusions

Food seeking behaviour may have a pre-birth origin. Maternal-fetal interaction around mealtimes could constitute an endocrine mediated communication, in the interests of maintaining optimal intrauterine conditions. Further research is warranted to explore this phenomenon and the potential influence of feeding on the temporal organisation of fetal activity in relation to growth.

Biophysical profile for fetal assessment in high risk pregnancies

BACKGROUND

A biophysical profile (BPP) includes ultrasound monitoring of fetal movements, fetal tone and fetal breathing, ultrasound assessment of liquor volume with or without assessment of the fetal heart rate. The BPP is performed in an effort to identify babies that may be at risk of poor pregnancy outcome, so that additional assessments of wellbeing may be performed, or labour may be induced or a caesarean section performed to expedite birth.

OBJECTIVES

To assess the effects of the BPP when compared with conventional monitoring (CTG only or MBPP) on pregnancy outcome in high-risk pregnancies.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (October 2007), CENTRAL (The Cochrane Library 2006, Issue 4), MEDLINE (1966 to November 2006), EMBASE (1974 to November 2006) and CINAHL (1980 to November 2006).

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials involving a comparison of fetal BPP with other forms of antepartum fetal assessment in women with high-risk pregnancies.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed eligibility, quality and extracted data.

MAIN RESULTS

We included five trials, involving 2974 women. Most trials were not of high quality. Although the overall incidence of adverse outcomes was low, available evidence from randomised controlled trials does not support the use of BPP as a test of fetal wellbeing in high-risk pregnancies. We found no significant differences between the groups in perinatal deaths (relative risk (RR) 1.33, 95% confidence interval (CI) 0.60 to 2.98) or in Apgar score less than seven at five minutes (RR 1.27, 95% CI 0.85 to 1.92). Combined data from the two high-quality trials suggest an increased risk of caesarean section in the BPP group RR 1.60, 95% CI 1.05 to 2.44, n = 280, interaction test P = 0.03. However, the number of participating women was relatively small (n = 280). Therefore, additional evidence is required in order to be definitive regarding the efficacy of this test in high-risk pregnancies. Furthermore, the impact of the BPP on other interventions, length of hospitalisation, serious short-term and long-term neonatal morbidity and parental satisfaction requires further evaluation.

AUTHORS' CONCLUSIONS

At present, there is insufficient evidence from randomised trials to support the use of BPP as a test of fetal wellbeing in high-risk pregnancies.

Changes in fetal motility as a result of congenital disorders: an overview

After 35 years of real-time two-dimensional sonography, can we now identify changes in fetal motility indicative of malfunction of the central nervous system in high-risk pregnancies? A literature search on motor assessment procedures (movements specified for body part (SMP), quantity, quality and behavioral state), and motor milestones obtained per fetus (with various congenital disorders) yielded 48 articles describing motility of 104 fetuses. In 67%, SMPs (especially isolated arm or leg movements, breathing and general movements) were assessed. Quantitative aspects were examined in 76%, qualitative aspects in 62% and behavioral states in two fetuses. Abnormal motility can be divided into two main subcategories: hypo- and hyperkinetic, demonstrating decreased variation in qualitative performance (reduced or increased, respectively, amplitude, speed and number of participating body parts, abnormal quantity (reduced or increased, respectively) and reduced differentiation into SMPs. Posture was affected in 40/60 hypokinetic and 4/44 hyperkinetic moving fetuses. The majority of the disorders resulted in an adverse outcome. Fourteen percent survived with a handicap, depending on the underlying disorder. The 16 disorders with hypokinetic motility had mainly an autosomal recessive etiology with no possibility of invasive prenatal diagnosis or conclusive sonographic structural anomalies, in contrast to the 17 disorders with hyperkinetic motility. Within the limitations of the studies, a deeper understanding of affected milestones in motor development can be obtained. Broadening motor assessment procedures from quantitative only to include qualitative aspects, differentiation of SMPs and behavioral states and emphasizing onset and continuity of motility before and after birth will enhance the reliability and predictive value of motility as a parameter in the assessment of fetal condition.

The importance of ‘awareness’ for understanding fetal pain

Our understanding of when the fetus can experience pain has been largely shaped by neuroanatomy. However, completion of the cortical nociceptive connections just after mid-gestation is only one part of the story. In addition to critically reviewing evidence for whether the fetus is ever awake or aware, and thus able to truly experience pain, we examine the role of endogenous neuro-inhibitors, such as adenosine and pregnanolone, produced within the feto-placental unit that contribute to fetal sleep states, and thus mediate suppression of fetal awareness. The uncritical view that the nature of presumed fetal pain perception can be assessed by reference to the prematurely born infant is challenged. Rigorously controlled studies of invasive procedures and analgesia in the fetus are required to clarify the impact of fetal nociception on postnatal pain sensitivity and neural development, and the potential benefits or harm of using analgesia in this unique setting.

Quantitative lingual, pharyngeal and laryngeal ultrasonography in swallowing research: a technical review

Because of its distinct advantage in radiation-free soft tissue imaging, ultrasonography has been widely used to study lingual, pharyngeal, hyoid, laryngeal, and even esophageal action during swallowing in individuals of all ages. Qualitative ultrasonographic observations have made considerable contributions to our understanding of deglutition. Quantitative ultrasonographic swallowing research has also grown by leaps and bounds over the years with advances in imaging technologies and analytical methodologies. As a technical primer for new investigators, this paper reviews the modem methods for quantitative analysis in ultrasonographic swallowing research. The intended outcome is a basic understanding of the application of ultrasonography with various analysis options to the quantitative study of the deglutitive action of selected upper aerodigestive structures. Though proven useful for swallowing research, ultrasonography has inherent limitations and methodological issues. Future technological advancement and sophisticated image processing and analysis algorithms will resolve some of these issues.

Diminished embryonic movements of developing embryo by direct exposure of sidestream whole smoke solutions

Embryonic movements (EM) are considered to be the first sign of life and cigarette smoking during pregnancy has been linked to affect EM. Exposure to sidestream smoke, produced from the emissions of a smoldering cigarette, may result in poor pregnancy outcome and increased risk of serious perinatal morbidity and mortality. In this study, the chicken embryo bioassay was used to systematically assess the effects of short-term exposure to sidestream whole smoke solutions (SSWSS) on EM, recorded in real time by a video camera for 60 min and each EM was counted for every 3-min interval. Application of different types of SSWSS to the embryos caused significant changes in all types of EM from 15 to 18 min of recording time. Extensive reduction (P<0.001) and some time complete stoppage of swing-like movements and whole-body movements were observed in almost all treated embryos. Our data clearly link between exposure of SSWSS and substantial decrease in EM. It is unclear whether nicotine and/or other ingredients present in sidestream smoke are responsible for these alterations in EM. This article provides an outline of the relevance of SSWSS on EM for evolutionary developmental biology and this assay can be used to investigate the complex mixtures with regard to their effects on EM.

Decreased fetal movements: background, assessment, and clinical management

A reduction or cessation of fetal movements (FMs) is frequently reported by pregnant women and causes concern and anxiety. However, the clinical significance of a history of reduced FMs remains unclear, and the assessment and management of these pregnancies is controversial. This article is a review of the literature on decreased FMs found in medline and the cochrane library using the search phrases: decreased FMs, perinatal outcome, FM monitoring, and fetal assessment. Formal counting of FMs by the pregnant woman could possibly identify the fetuses, which are at risk of compromise, thus allowing for appropriate action. However, the benefit of this intervention has not been definitely proven. Cardiotocography, umbilical/uterine artery Doppler velocimetry, and ultrasonography have been used for antepartum fetal assessment in pregnancies with decreased FMs, but the evidence of a clinical benefit is limited. The effects of fetal assessment with vibroacoustic stimulation and biophysical profile are unknown and should be further evaluated. Present recommendations on the management of pregnancies with decreased FMs are based on limited and inconsistent scientific evidence. There is a need for further well-designed studies in order to provide evidence-based guidelines in the future.

Forty years of obstetric ultrasound 1957-1997: from A-scope to three dimensions

In this article, we record the history of obstetric ultrasound as it developed worldwide in the second half of the twentieth century. The technological advances during this period saw the evolution of equipment from the original adapted metal flaw detectors producing a simple A-scan to the modern, purpose built, real-time colour flow machines with three-dimensional capability (Fig. 1). Clinically, ultrasound began as a research tool, but the poor quality of the images led to the ridicule of many of the early investigators. However, because of their perseverance, ultrasound developed into an imaging modality providing immense diagnostic capabilities and facilitating with precision many invasive procedures, diagnostic and therapeutic, both of which have made significant contributions to patient care. In this history, we recall the people, the personalities, and the problems they encountered during the development of ultrasound and how these problems were resolved, so that ultrasound now is available for use in the care of pregnant women throughout the developed world.

Abnormal antenatal ultrasound findings and subsequent handicap

The modern ultrasound technique in its various modes, real-time B-mode, M-mode, continuous and pulsed wave Doppler ultrasound, makes it possible to study in detail the fetal anatomy and function in utero. Fetometry allows for the evaluation of fetal size and growth and for detecting growth-retarded or macrosomic fetuses. Ultrasound seems, at present, to be the best method available in the detection of the growth-retarded fetus who is at risk of developing perinatal complications and subsequent handicap. Ultrasound can also be used when fetal growth retardation is suspected on clinical grounds. An absolute prerequisite for the proper use of ultrasound fetometry is the estimation of gestational age in early pregnancy. The high resolution of modern ultrasound scanners allows the antenatal detection of even minor fetal structural abnormalities. When lethal malformations are detected early in pregnancy, selective termination of pregnancy can be considered. Fetal abnormality detected in late pregnancy allows for optimal timing and mode of delivery leading to improved management and outcome, thus lowering the risks of subsequent handicap. Ultrasound examination of the extrafetal structures, e.g. umbilical cord, placenta and amniotic fluid volume, may add valuable clinical information. The finding of severe oligohydramnios is associated with increased perinatal mortality and morbidity. Fetal circulation can be evaluated by using the combination of real-time and pulsed Doppler ultrasound or, alternatively, by employing continuous wave Doppler ultrasound alone. Pathological changes in the blood velocity waveforms recorded from the fetal and umbilical arteries may signify very early signs of fetal hypoxia. The method has the potential of becoming a useful clinical method for fetal surveillance. The guidelines for a proper application in the perinatal medicine of the Doppler method have, however, not yet been established. In fetuses with cardiac arrhythmia and/or cardiac malformation, the Doppler investigation of the fetal circulation can be used to evaluate the haemodynamic alterations and, in cases of intrauterine treatment, to supervise and monitor the therapeutic effects. Fetal motor function can be followed and quantified with real-time ultrasound. Abnormal motor activity might indicate bad perinatal outcome. The predictive capacity of the test is increased when several variables are combined (e.g. the fetal biophysical profile score).(ABSTRACT TRUNCATED AT 400 WORDS)

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.