Talk:Fetal Development

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Cite this page: Hill, M.A. (2024, June 13) Embryology Fetal Development. Retrieved from


Turk E, van den Heuvel MI, Benders MJ, de Heus R, Franx A, Manning JH, Hect JL, Hernandez-Andrade E, Hassan SS, Romero R, Kahn RS, Thomason ME & van den Heuvel MP. (2019). Functional connectome of the fetal brain. J. Neurosci. , , . PMID: 31685648 DOI. Functional connectome of the fetal brain.

Abstract Large-scale functional connectome formation and re-organization is apparent in the second trimester of pregnancy, making it a crucial and vulnerable time window in connectome development. Here we identified which architectural principles of functional connectome organization are initiated prior to birth, and contrast those with topological characteristics observed in the mature adult brain. A sample of 105 pregnant women participated in human fetal resting-state fMRI studies (fetal gestational age between 20 and 40 weeks). Connectome analysis was used to analyze weighted network characteristics of fetal macroscale brain wiring. We identified efficient network attributes, common functional modules and high overlap between the fetal and adult brain network. Our results indicate that key features of the functional connectome are present in the second and third trimesters of pregnancy. Understanding the organizational principles of fetal connectome organization may bring opportunities to develop markers for early detection of alterations of brain function.SIGNIFICANCE STATEMENTThe fetal to neonatal period is well known as a critical stage in brain development. Rapid neurodevelopmental processes establish key functional neural circuits of the human brain. Prenatal risk factors may interfere with early trajectories of connectome formation and thereby shape future health outcomes. Recent advances in MRI have made it possible to examine fetal brain functional connectivity. In this study, we evaluate the network topography of normative functional network development during connectome genesis in utero Understanding the developmental trajectory of brain connectivity provides a basis for understanding how the prenatal period shapes future brain function and disease dysfunction. Copyright © 2019 the authors. PMID: 31685648 DOI: 10.1523/JNEUROSCI.2891-18.2019

Fetal brain growth portrayed by a spatiotemporal diffusion tensor MRI atlas computed from in utero images

Neuroimage. 2019 Jan 15;185:593-608. doi: 10.1016/j.neuroimage.2018.08.030. Epub 2018 Aug 30.

Khan S1, Vasung L2, Marami B3, Rollins CK4, Afacan O5, Ortinau CM6, Yang E5, Warfield SK5, Gholipour A5. Author information Abstract Altered structural fetal brain development has been linked to neuro-developmental disorders. These structural alterations can be potentially detected in utero using diffusion tensor imaging (DTI). However, acquisition and reconstruction of in utero fetal brain DTI remains challenging. Until now, motion-robust DTI methods have been employed for reconstruction of in utero fetal DTIs. However, due to the unconstrained fetal motion and permissible in utero acquisition times, these methods yielded limited success and have typically resulted in noisy DTIs. Consequently, atlases and methods that could enable groupwise studies, multi-modality imaging, and computer-aided diagnosis from in utero DTIs have not yet been developed. This paper presents the first DTI atlas of the fetal brain computed from in utero diffusion-weighted images. For this purpose an algorithm for computing an unbiased spatiotemporal DTI atlas, which integrates kernel-regression in age with a diffeomorphic tensor-to-tensor registration of motion-corrected and reconstructed individual fetal brain DTIs, was developed. Our new algorithm was applied to a set of 67 fetal DTI scans acquired from healthy fetuses each scanned at a gestational age between 21 and 39 weeks. The neurodevelopmental trends in the fetal brain, characterized by the atlas, were qualitatively and quantitatively compared with the observations reported in prior ex vivo and in utero studies, and with results from imaging gestational-age equivalent preterm infants. Our major findings revealed early presence of limbic fiber bundles, followed by the appearance and maturation of projection pathways (characterized by an age related increase in FA) during late 2nd and early 3rd trimesters. During the 3rd trimester association fiber bundles become evident. In parallel with the appearance and maturation of fiber bundles, from 21 to 39 gestational weeks gradual disappearance of the radial coherence of the telencephalic wall was qualitatively identified. These results and analyses show that our DTI atlas of the fetal brain is useful for reliable detection of major neuronal fiber bundle pathways and for characterization of the fetal brain reorganization that occurs in utero. The atlas can also serve as a useful resource for detection of normal and abnormal fetal brain development in utero.

PMID: 30172006 PMCID: PMC6289660 [Available on 2020-01-15] DOI: 10.1016/j.neuroimage.2018.08.030

The role of three-dimensional ultrasonography fetal lung volume measurement in the prediction of neonatal respiratory function outcome

J Matern Fetal Neonatal Med. 2019 Feb;32(4):660-665. doi: 10.1080/14767058.2017.1387898. Epub 2017 Oct 12.

Maged A1, Youssef G1, Hussien A1, Gaafar H1, Elsherbini M1, Elkomy R1, Eid M1, Abd El-Hamid N1, Abdel-Razek AR2. Author information Abstract BACKGROUND: Respiratory distress is commonly encountered among premature babies immediately after birth resulting in significant neonatal morbidity or mortality.

OBJECTIVES: To evaluate the possible correlation between three dimensional fetal lung volumes (FLVs) and neonatal respiratory outcomes.

STUDY DESIGN: A cohort study included 100 pregnant women who participated in the study and were divided into two groups; group A (n: 50 - women pregnant ±34-37 weeks) and group B (n: 50 - women pregnant ±37+1 to 40 weeks). A three dimensional measurement of the right fetal lung was made using virtual organ computer-aided analysis (VOCAL) software then correlated to neonatal respiratory functions namely Apgar score at birth and the occurrence of respiratory distress syndrome (RDS).

RESULTS: In group A, FLV was negatively correlated with Apgar score and the occurrence of RDS. In group B, FLV showed no statistical correlation with Apgar score and the occurrence of RDS.

CONCLUSIONS: Three dimensional fetal lung volumes might be an accurate noninvasive predictor for the development of RDS among preterm fetuses.

KEYWORDS: Lung volume; VOCAL; respiratory distress syndrome PMID: 28969488 DOI: 10.1080/14767058.2017.1387898


Stresses and strains on the human fetal skeleton during development

J R Soc Interface. 2018 Jan;15(138). pii: 20170593. doi: 10.1098/rsif.2017.0593.

Verbruggen SW1, Kainz B2, Shelmerdine SC3, Hajnal JV4, Rutherford MA5, Arthurs OJ6, Phillips ATM7, Nowlan NC8.


Mechanical forces generated by fetal kicks and movements result in stimulation of the fetal skeleton in the form of stress and strain. This stimulation is known to be critical for prenatal musculoskeletal development; indeed, abnormal or absent movements have been implicated in multiple congenital disorders. However, the mechanical stress and strain experienced by the developing human skeleton in utero have never before been characterized. Here, we quantify the biomechanics of fetal movements during the second half of gestation by modelling fetal movements captured using novel cine-magnetic resonance imaging technology. By tracking these movements, quantifying fetal kick and muscle forces, and applying them to three-dimensional geometries of the fetal skeleton, we test the hypothesis that stress and strain change over ontogeny. We find that fetal kick force increases significantly from 20 to 30 weeks' gestation, before decreasing towards term. However, stress and strain in the fetal skeleton rises significantly over the latter half of gestation. This increasing trend with gestational age is important because changes in fetal movement patterns in late pregnancy have been linked to poor fetal outcomes and musculoskeletal malformations. This research represents the first quantification of kick force and mechanical stress and strain due to fetal movements in the human skeleton in utero, thus advancing our understanding of the biomechanical environment of the uterus. Further, by revealing a potential link between fetal biomechanics and skeletal malformations, our work will stimulate future research in tissue engineering and mechanobiology. KEYWORDS: biomechanical stimuli; cine-MRI; finite element analysis; joint biomechanics; musculo-skeletal development

PMID: 29367236 DOI: 10.1098/rsif.2017.0593


Accelerated Fetal Growth Prior to Diagnosis of Gestational Diabetes Mellitus: A Prospective Cohort Study of Nulliparous Women

OBJECTIVE To determine whether fetal overgrowth precedes the diagnosis of gestational diabetes mellitus (GDM) and to quantify the interrelationships among fetal overgrowth, GDM, and maternal obesity.

RESULTS Of 4,069 women, 171 (4.2%) were diagnosed with GDM at ≥28 wkGA. There was no association between fetal biometry at 20 wkGA and subsequent maternal diagnosis of GDM. However, at 28 wkGA, there was an increased risk of AC >90th percentile (adjusted relative risk 2.05 [95% CI 1.37–3.07]) and HC-to-AC ratio <10th percentile (1.97 [1.30–2.99]). Maternal obesity showed similar associations at 28 wkGA (2.04 [1.62–2.56] and 1.46 [1.12–1.90], respectively). The combination of GDM and obesity was associated with an approximately fivefold risk of AC >90th (4.52 [2.98–6.85]) and approximately threefold risk of HC-to-AC ratio <10th percentile (2.80 [1.64–4.78]) at 28 wkGA. Fetal AC >90th percentile at 28 weeks was associated with an approximately fourfold risk of being large for gestational age at birth.

CONCLUSIONS Diagnosis of GDM is preceded by excessive growth of the fetal AC between 20 and 28 wkGA, and its effects on fetal growth are additive with the effects of maternal obesity.


Racial/ethnic standards for fetal growth: the NICHD Fetal Growth Studies

Am J Obstet Gynecol. 2015 Oct;213(4):449.e1-449.e41. doi: 10.1016/j.ajog.2015.08.032.

Buck Louis GM1, Grewal J2, Albert PS2, Sciscione A3, Wing DA4, Grobman WA5, Newman RB6, Wapner R7, D'Alton ME7, Skupski D8, Nageotte MP9, Ranzini AC10, Owen J11, Chien EK12, Craigo S13, Hediger ML2, Kim S2, Zhang C2, Grantz KL2.


OBJECTIVE: Fetal growth is associated with long-term health yet no appropriate standards exist for the early identification of undergrown or overgrown fetuses. We sought to develop contemporary fetal growth standards for 4 self-identified US racial/ethnic groups. STUDY DESIGN: We recruited for prospective follow-up 2334 healthy women with low-risk, singleton pregnancies from 12 community and perinatal centers from July 2009 through January 2013. The cohort comprised: 614 (26%) non-Hispanic whites, 611 (26%) non-Hispanic blacks, 649 (28%) Hispanics, and 460 (20%) Asians. Women were screened at 8w0d to 13w6d for maternal health status associated with presumably normal fetal growth (aged 18-40 years; body mass index 19.0-29.9 kg/m(2); healthy lifestyles and living conditions; low-risk medical and obstetrical history); 92% of recruited women completed the protocol. Women were randomized among 4 ultrasonography schedules for longitudinal fetal measurement using the Voluson E8 (GE Healthcare, Milwaukee, WI). In-person interviews and anthropometric assessments were conducted at each visit; medical records were abstracted. The fetuses of 1737 (74%) women continued to be low risk (uncomplicated pregnancy, absent anomalies) at birth, and their measurements were included in the standards. Racial/ethnic-specific fetal growth curves were estimated using linear mixed models with cubic splines. Estimated fetal weight (EFW) and biometric parameter percentiles (5th, 50th, 95th) were determined for each gestational week and comparisons made by race/ethnicity, with and without adjustment for maternal and sociodemographic factors. RESULTS: EFW differed significantly by race/ethnicity >20 weeks. Specifically at 39 weeks, the 5th, 50th, and 95th percentiles were 2790, 3505, and 4402 g for white; 2633, 3336, and 4226 g for Hispanic; 2621, 3270, and 4078 g for Asian; and 2622, 3260, and 4053 g for black women (adjusted global P < .001). For individual parameters, racial/ethnic differences by order of detection were: humerus and femur lengths (10 weeks), abdominal circumference (16 weeks), head circumference (21 weeks), and biparietal diameter (27 weeks). The study-derived standard based solely on the white group erroneously classifies as much as 15% of non-white fetuses as growth restricted (EFW <5th percentile). CONCLUSION: Significant differences in fetal growth were found among the 4 groups. Racial/ethnic-specific standards improve the precision in evaluating fetal growth. Published by Elsevier Inc. KEYWORDS: birthweight; epidemiology; estimated fetal growth; fetal growth; pregnancy

PMID 26410205



The quality of fetal arm movements as indicators of fetal stress

Early Hum Dev. 2010 Oct 12. [Epub ahead of print]

Reissland N, Francis B.

Department of Psychology, University of Durham, Science Site, South Road, Durham DH1 3LE, UK. Abstract

BACKGROUND: Although a number of studies have found that maternal stress affects the fetus, it is unclear whether jerky fetal movements observed on ultrasound scans are indicative of fetal stress, or whether they are part of normal development.

AIMS: The present study was designed to examine the relationship between jerky fetal arm movements in relation to fetal age and stress.

METHODS: Video recordings were made of routine ultrasound scans of 57 fetuses (age range 8 to 33weeks) classified into three age groups: 1st trimester (8-12weeks, N=9), 2nd trimester (13-24weeks, N=38), and 3rd trimester (26-33weeks, N=10). Following previous research on stress behaviour in neonates, a fetal index of stress was derived from frequency of hiccup, back arch and rhythmical mouthing.

RESULTS: Results indicated that while stress level was unrelated to fetal age, jerkiness of arm movements was significantly associated with the fetal stress index but not age.

CONCLUSIONS: Our findings suggest that jerky arm movements in fetuses are suggestive of fetal stress. Copyright © 2010 Elsevier Ltd. All rights reserved.

PMID: 20947272


Autopsy standards for fetal lengths and organ weights of an Australian perinatal population

Pathology. 2009;41(6):515-26.

Phillips JB, Billson VR, Forbes AB.

Department of Anatomical Pathology, Royal Women's Hospital, Melbourne, Melbourne, Victoria, Australia. Abstract AIMS: This study aims to establish a complete and accurate set of Australian reference ranges to be used during the routine perinatal post-mortem examination. Eighteen routinely measured parameters will be analysed for each gestational age from 12 weeks to 42 weeks inclusive.

METHODS: A retrospective review was performed of all perinatal and neonatal autopsies conducted at the Royal Women's Hospital (RWH), Melbourne, between 1 January 2001 and 31 December 2006. A total of 1116 post-mortem examination reports were analysed for this study. Established study design, technical and statistical methodologies were followed.

RESULTS: Reference ranges comprising mean and standard deviation have been produced, together with the 5th, 50th and 95th percentiles for all parameters at each gestational age. Graphs demonstrating these data have been developed for each parameter.

CONCLUSION: This study has established a complete set of reference ranges for parameters measured at perinatal post-mortem examinations. As the sample population used is truly representative of the mixed immigrant population present in Australian society, the reference ranges and percentiles produced in this study will be valuable for all perinatal pathologists.

PMID: 19588281


New charts for ultrasound dating of pregnancy and assessment of fetal growth: longitudinal data from a population-based cohort study

Ultrasound Obstet Gynecol. 2008 Apr;31(4):388-96.

Verburg BO, Steegers EA, De Ridder M, Snijders RJ, Smith E, Hofman A, Moll HA, Jaddoe VW, Witteman JC.

The Generation R Study Group, Erasmus Medical Center, Sophia Children's Hospital, University Medical Center Rotterdam, Rotterdam, The Netherlands.


OBJECTIVES: Correct assessment of gestational age and fetal growth is essential for optimal obstetric management. The objectives of this study were, first, to develop charts for ultrasound dating of pregnancy based on crown-rump length and biparietal diameter and, second, to derive reference curves for normal fetal growth based on biparietal diameter, head circumference, transverse cerebellar diameter, abdominal circumference and femur length from 10 weeks of gestational age onwards.

METHODS: A total of 8313 pregnant women were included for analysis in this population-based prospective cohort study. All women had repeated ultrasound assessments to examine fetal growth.

RESULTS: Charts for ultrasound dating of pregnancy, based on crown-rump length and biparietal diameter, were derived. Internal validation with the actual date of delivery showed that ultrasound imaging provided reliable gestational age estimates. Up to 92% of deliveries took place within 37-42 weeks of gestation if gestational age was derived from ultrasound data, compared with 87% based on a reliable last menstrual period. The earlier the ultrasound assessment the more accurate the prediction of date of delivery. After 24 weeks of gestation a reliable last menstrual period provided better estimates of gestational age. Reference curves for normal fetal growth from 10 weeks of gestational age onwards were derived.

CONCLUSIONS: Charts for ultrasound dating of pregnancy and reference curves for fetal biometry are presented. The results indicate that, up to 24 weeks of pregnancy, dating by ultrasound examination provides a better prediction of the date of delivery than does last menstrual period. The earlier the ultrasound assessment in pregnancy, preferably between 10 and 12 weeks, the better the estimate of gestational age.

Copyright (c) 2008 ISUOG. Published by John Wiley & Sons, Ltd.

PMID: 18348183


Quantitative standards for fetal and neonatal autopsy

Am J Clin Pathol. 2006 Aug;126(2):256-65.

Archie JG, Collins JS, Lebel RR.

Office of Epidemiology, Greenwood Genetic Center, Greenwood, SC, USA.

Abstract Growth curves are essential for determining whether growth parameters lie within normal ranges. In the case of fetal and neonatal autopsy, relevant data are scattered across many publications, and few sources examine a large enough sample to be considered definitive. To ameliorate these inadequacies, regressions were created incorporating data from multiple sources both to increase accuracy and to condense available data into a single standard. When measurements were not well studied, the best available published standards are given. These regressions provide a valuable tool for clinicians who need to understand the significance of measurements obtained during autopsy.

PMID: 16891202

--Mark Hill 15:59, 16 April 2010 (EST) Good set of data for fetal growth with online calculator. Uses Postmenstrual Gestational Ages (LMP)


Reference values for second trimester fetal and neonatal organ weights and measurements

Pediatr Dev Pathol. 2003 Mar-Apr;6(2):160-7. Epub 2003 Jan 29.

Hansen K, Sung CJ, Huang C, Pinar H, Singer DB, Oyer CE.

Department of Pathology, Women and Infants Hospital of Rhode Island and Brown Medical School, 101 Dudley Street, Providence, RI 02905, USA. Abstract To establish accurate reference ranges for the entire second trimester, we documented organ weights, body weight, and linear measurements for 597 fetuses and neonates with gestational ages ranging from 12 to 26 wk. We determined the mean and standard deviation for weights and measurements at each week of gestation using the StatView trade mark SE + Graphics statistical program. The analyses revealed a linear correlation between the gestational age and, respectively, the toe-heel length, crown-rump length, and crown-heel length. Body and organ weights increase at varying rates throughout the second trimester. The data correlate well with weights and measurements previously published for the latter half of the second trimester, and extend these reference ranges to encompass the entire second trimester.

PMID: 12548377

Myelination occurs rapidly in the first year of life and overall adult patterns are present at age 2 years

Effect of trihalomethane exposure on fetal development. Wright JM, Schwartz J, Dockery DW. Occup Environ Med. 2003 Mar;60(3):173-80. PMID: 12598663

Lifetime consequences of abnormal fetal pancreatic development. Holemans K, Aerts L, Van Assche FA. J Physiol. 2003 Feb 15;547(Pt 1):11-20. Epub 2003 Jan 17. Review. PMID: 12562919

Development of the innervation and airway smooth muscle in human fetal lung

Human and porcine fetal airways have been shown to contract spontaneously from the first trimester, the latter also contracting in response to neural stimulation. Our object was to map immunohistochemically the innervation and its relationship to the airway smooth muscle (ASM) in the human fetal lung from early gestation to the postnatal period. Whole mounts of the bronchial tree were stained with antibodies to the pan-neuronal marker protein gene product 9.5, the Schwann cell marker S-100, and the ASM contractile protein alpha-actin, and imaged using confocal microscopy. By the end of the embryonic period (53 d gestation), the branching epithelial tubules in the primordial lung were covered with ASM to the base of the terminal sacs. An extensive plexus of nerve trunks containing nerve bundles, forming ganglia, and Schwann cells ensheathed the ASM. By 16 wk (canalicular stage), maturation of the innervation was advanced with two major nerve trunks running the length of the bronchial tree, giving rise to varicosed fibers lying on the ASM. An extensive nerve plexus in the mucosa was also present. The distal airways of infants who had died of Sudden Infant Death Syndrome were also covered with smooth muscle and were well innervated. Thus, an essentially complete coat of ASM and an abundant neural plexus ensheathing the airways are an integral part of the branching epithelial tubules from early in lung development.

Various Fetal Parameters

Cetin E, Malas MA, Albay S, Cankara N. Abstract The development of stomach during the fetal period. Surg Radiol Anat. 2006 Oct;28(5):438-46. Epub 2006 Aug 12. PMID: 16906359 [PubMed - indexed for MEDLINE] 7:

Malas MA, Ungör B, Tağil SM, Sulak O. Abstract Determination of dimensions and angles of mandible in the fetal period. Surg Radiol Anat. 2006 Aug;28(4):364-71. Epub 2006 Mar 28. PMID: 16568218 [PubMed - indexed for MEDLINE] 8:

Vlajković S, Vasović L, Daković-Bjelaković M, Cukuranović R. Abstract Age-related changes of the human fetal kidney size. Cells Tissues Organs. 2006;182(3-4):193-200. PMID: 16914921 [PubMed - indexed for MEDLINE] 9:

Albay S, Malas MA, Cetin E, Cankara N, Karahan N. Abstract Development of the liver during the fetal period. Saudi Med J. 2005 Nov;26(11):1710-5. PMID: 16311653 [PubMed - indexed for MEDLINE] 10:

Sari A, Ahmetoglu A, Dinc H, Saglam A, Kurtoglu U, Kandemir S, Gümele HR. Abstract Fetal biometry: size and configuration of the third ventricle. Acta Radiol. 2005 Oct;46(6):631-5. PMID: 16334847 [PubMed - indexed for MEDLINE] 11:

Vignolo M, Ginocchio G, Parodi A, Torrisi C, Pistorio A, Venturini PL, Aicardi G, De Biasio P. Abstract Fetal spine ossification: the gender and individual differences illustrated by ultrasonography. Ultrasound Med Biol. 2005 Jun;31(6):733-8. PMID: 15936488 [PubMed - indexed for MEDLINE] 12:

Uysal II, Karabulut AK, Salbacak A, Büyükmumcu M, Seker M. Abstract Correlation between developmental stages of the human heart and gestational ages. Saudi Med J. 2005 Apr;26(4):531-6. PMID: 15900354 [PubMed - indexed for MEDLINE] 13:

Lampl M, Kuzawa CW, Jeanty P. Abstract Growth patterns of the heart and kidney suggest inter-organ collaboration in facultative fetal growth. Am J Hum Biol. 2005 Mar-Apr;17(2):178-94. PMID: 15736176 [PubMed - indexed for MEDLINE] 14:

Al Atawi F, Warsy A, Babay Z, Addar M. Abstract Fetal sex and leptin concentrations in pregnant females. Ann Saudi Med. 2005 Mar-Apr;25(2):124-8. PMID: 15977690 [PubMed - indexed for MEDLINE] 15:

Vlajković S, Daković-Bjelaković M, Cukuranović R, Popović J. Abstract Evaluation of absolute volume of human fetal kidney's cortex and medulla during gestation. Vojnosanit Pregl. 2005 Feb;62(2):107-11. PMID: 15787163 [PubMed - indexed for MEDLINE] 16:

Perni SC, Predanic M, Cho JE, Kalish RB, Chasen ST. Abstract Association of amniotic fluid index with estimated fetal weight. J Ultrasound Med. 2004 Nov;23(11):1449-52; quiz 1453. PMID: 15498909 [PubMed - indexed for MEDLINE]


Fetal and neonatal hand movement

Phys Ther. 1999 Jan;79(1):24-39.

Sparling JW1, Van Tol J, Chescheir NC.

Abstract BACKGROUND AND PURPOSE: Fetal movement occurs early in human gestation and can be observed by ultrasound imaging. This was a descriptive study of fetal hand movements from 14 weeks of gestation to postnatal day 1. The purpose of the study was to identify specific hand movements and their developmental trends in order to better understand low-risk human development. SUBJECTS: Twenty-one women with low-risk pregnancies were identified from a university obstetrics clinic. Their fetuses or neonates were the focus of this study. METHODS: Ultrasound imaging was used at 14, 20, 26, 32, and 37 weeks of gestation, and videotaping was used at 1 day after birth. Between 12 and 16 minutes of usable imaging was obtained at each fetal age, and 24 minutes of videotape was collected neonatally. The duration and frequency of 7 hand movements were determined and reliably scored. Nonparametric analyses were used. RESULTS: Fetal and neonatal movements did not appear to be random, and they appeared to be directed or aimed at specific targets. Fetal movement was variable throughout gestation. Differences occurred between fetal and neonatal data. Durations of certain hand movements provided data that exhibited some developmental trends, such as decreasing linear trends and regression-type U curves. Fetal movements to or at the head and face and the observations scored at 32 weeks of gestation were the best predictors of neonatal movement. CONCLUSION AND DISCUSSION: Results suggest the potential for fetal movement to be observed and scored reliably, with scores used to further our understanding of the development of human movement. PMID: 9920189