This page links to all ultrasound movies of live normal human embryos. Ultrasound imaging began in the 1950's but it was only with the application of computer analysis beginning in the 1980's that more detailed images could be generated.
Parents now commonly see ultrasound movies or images in the first trimester and clinically this is a non-invasive prenatal diagnostic tool for detection of abnormalities as well as a method of staging (ageing) and checking growth. Ultrasound can also be used in combination with other techniques to locate both embryo and placenta for other prenatal tests (More? Prenatal Diagnosis).
The ultrasound technique can be used at any stage during pregnancy for embryo and placenta monitoring (More? about ultrasound). The ultrasound movies can be viewed in two ways. Firstly, click the image or text link opens a new page with both the movie and a more detailed text description of features. Secondly, clicking on the quicktime link will open the movie alone on a new page. At the bottom of this current page is further ultrasound information and links to internet ultrasound sites.
Abnormal developmental ultrasound and features are listed on a separate page (More? Abnormal Ultrasound) all content is for educational use only.
Special thanks to Dr Andrew McLennan, Foetal Medicine Unit, Royal North Shore Hospital for original video materials.
Page Links: Introduction | Some Recent Findings | Ultrasound Research | Other Imaging Techniques | Human 7 Week Ultrasound | Human 7 Week Twins | Human 8 Week | Human 12 Week | Human 12 Week Fetal Heart Rate | Human 3D Imaging | Human 12 Week 4D | About Ultrasound | Ultrasound Measurements | Other Ultrasound Applications | Ultrasound Links | References | Glossary | Terms
Picone O, Simon I, Benachi A, Brunelle F, Sonigo P. Comparison between ultrasound and magnetic resonance imaging in assessment of fetal cytomegalovirus infection. Prenat Diagn. 2008 Jun 13.
"MRI can provide important additional information with regard to abnormal gyration, cerebellar hypoplasia, or abnormal signal in white matter. It is certainly useful in the assessment of fetuses with extracerebral features without brain abnormalities detected with ultrasounds. If the fetal ultrasound is strictly normal in an infected fetus, MRI may not detect brain anomalies; however, it seems difficult to not perform this noninvasive procedure."
Ultrasound imaging began in the 1950's but it was only with the application of computer analysis beginning in the 1980's that more detailed images could be generated. The increasing quality of ultrasonic equipment and computing allows today realtime 3D scans and calculations of fetal measurements as well as doppler measurement of heart rates.
There are a range of other imaging techniques to study development and used in developmental research.
Other developmental research imaging techniques include:
high frequency ultrasound or High Intensity Focused Ultrasound (HIFU)
positron emission tomography (PET)
single photon emission computed tomography
Movie of 7 week human embryo in utero.
The embryo's head, heart and placental attachment can be seen.
Quicktime: 7wk.mov (1.3 Mb)
Movie of 7 week human embryo twins in utero.
Embryos (outlined in red ring) show separate placental attachments.
Quicktime: 7twk.mov (1.0 Mb)
Movie of 8 week human embryo in utero.
The embryo's head, heart (beating), spine, limb buds and placental attachment can be seen. Compare the size and features visible on the embryo with the earlier 7 week embryo.
Quicktime: 8wk.mov (1.8 Mb)
Movie of 12 week human embryo in utero.
The fetus head, heart (beating), spine, limb buds and placental attachment can be seen. Compare the size and features visible on the embryo with the earlier 8 and 7 week embryo.
Quicktime: 12wk.mov (800 Kb)
Movie of 12 week human embryo in utero.
The 12 week fetal heart beat can be seen in the ultrasound and a heart rate calculated from the doppler image.
Quicktime: 12wkFHR.mov (848 Kb)
(More? Notes- Fetal Heart Rate)
No movie link, page describes how 3D ultrasound images are generated. Which is relevant for understanding how 4D imaging movies are made.
Different body tissues reflect sound waves differently. In ultrasound, a beam of sound waves (frequency 3 to 10 MHz) are passed through the body, the reflected waves are analysed by a computer, and an image is then generated on a display screen. The sound source is usually a transducer placed on the surface of the abdomen. (More? Terms | Patient Data | 3D Imaging)
The thumbnail image above is linked to an ultrasound scan through the fetal trunk to measure abdominal circumference (AC).
There can be number of different parameters, depending on gestational age, that are commonly recorded during an ultrasound procedure. These measurements (and ratios) include embryonic/fetal size and key lengths and sizes of specific structures, fetal membrane sizes/volumes, placental location/size. In addition, general body movements, including heartbeat, can be observed. (More? Terms)
Embryonic/Fetal Size: crown-rump length (CRL), biparietal diameter (BPD), abdominal circumference (AC)
Embryonic/Fetal Structures: femur length (FL), head circumference, nuchal translucency, heart size/rate
Fetal Membrane: gestational sac diameter (GS), yolk sac diameter (YS), meconium peritonitis, umbilical cord stricture
Placenta: location, size, umbilical cord stricture
Ultrasound can be used for many different non-invasive clinical applications. Those abnormalities that relate to embryology include ovarian (ovarian cancer, hemorrhagic corpus luteum cyst) and uterine (uterine fibroids, rudimentary uterine horn, endometrial cancer)
These links are to external sites with information about ultrasound and require internet connection.
Smithsonian Videohistory Collection The History of Acuson Ultrasound Machines (RU 9593)
Some excellent fetal imaging from the 2 links below.
Additional internet resources.
Keret D, Bronshtein M, Wientraub S. Prenatal diagnosis of musculoskeletal anomalies. Clin Orthop Relat Res. 2005 May;(434):8-15. Review.
Bailao LA, Osborne NG, Rizzi MC, Bonilla-Musoles F, Duarte G, Bailao TC. Ultrasound markers of fetal infection part 1: viral infections. Ultrasound Q. 2005 Dec;21(4):295-308.
Swire MN, Castro-Aragon I, Levine D. Various sonographic appearances of the hemorrhagic corpus luteum cyst. Ultrasound Q. 2004 Jun;20(2):45-58. Review.
Togashi K. Ovarian cancer: the clinical role of US, CT, and MRI. Eur Radiol. 2003 Dec;13 Suppl 4:L87-104. Review.
Jain KA. Sonographic spectrum of hemorrhagic ovarian cysts. J Ultrasound Med. 2002 Aug;21(8):879-86.
Search Jun 2008 "prenatal ultrasound" 25,461 reference articles of which 3,126 were reviews.
abdominal circumference - An ultrasound measurement of Abdominal Circumference (AC) is used to determine fetal age and normal development (small/large/abnormal) parameters. Measured at the outer edge of the circumference of the body plane in which the portal vein or stomach can be visualized in a tangential section. Abdominal Circumference of less than 31 cm at 36 to 40 weeks gestation is a predictor of intrauterine growth retardation (IUGR).
biparietal diameter - An ultrasound measurement of Biparietal Diameter (BPD) is used to determine fetal age and normal development (small/large/abnormal) parameters. Measured as the diameter between the 2 sides of the head, used in clinical ultrasound measurements after 13 weeks (2.4 cm) to term (9.5 cm).
femur length - An ultrasound measurement of Femur Length (FL) is used to determine fetal age and normal development (small/large/abnormal) parameters. The femur is the longest bone in the body and measurements and reflects the longitudinal growth of the fetus (approximately 14 weeks 1.5 cm - term 7.8 cm).
head circumference - An ultrasound measurement of Head Circumference (HC) is used to determine fetal age and normal development (small/large/abnormal) parameters. Measured as an ellipse in a horizontal section at the level of the thalamus and the cavum septi pellucidi.