The document discusses the anatomy and abnormalities of the umbilical cord that can be identified on prenatal ultrasound. It provides details on the normal structure of the cord including the umbilical vessels and Wharton's jelly. Common abnormalities discussed include short or long cord length, umbilical cord cysts, single umbilical artery, velamentous or furcate cord insertion, and umbilical cord coiling abnormalities. Associations of various cord abnormalities with adverse pregnancy outcomes are also summarized.

3. Earlier it was just counting the number of vessel but now
playing an important role in haemodynamics.
It is actively involved in indentifying important process like
1. Foetal growth restriction.
2. Preeclampsia.
3. Diabetes.
4. Chromosomal defect or genetic syndrome.

4. 50-60 cms long usually covered by
single layer of amniotic epithelium.
vessels are embeded in wharton’s
jelly.
The characteristic structure of umbilical
cord is determined by the helical course
of arteries around vein. Between umbilical
ring and placental insertion.

5. WHARTON’S JELLY
 Jel like structure.
 No proper vasculature.
Functions - give flexibility and strength to cord.
Transfer of water & metabolites between amniotic fluid and umbilical
cord vessels. active throughout pregnancy.
Helps in remodeling and embryogenesis.
Umbilical vein
Umbilical
artery

6. Structure is very dynamic and Influenced by a number of factors
including –
1) Gestational age.
2) Amount of amniotic fluid and it’s composition.
3) Foetal movements.
4) Foeto placental haemodynamics.
5) Maternal complication during pregnancy
The evaluation of umbilical cord can be done long axis view or
transverse view, Cross sectional view is more appropriate because it
allows quantification not only of umbilical vessel size but also amount of
Wharton’s jelly.

7. Cord begins to form at 5 weeks of gestation it becomes longer until
28 weeks of pregnancy until it reaches average length of 22 to 24
inches (55 -60 cm.).
Normal cord length is 50-60 cm.

8. CORD LENGTH

9. SHORT CORD
< 35 cm is defined as short cord, may lead to foetal distress, placental
abruption, prolonged labour.
LONG CORD
> 80 cm is defined as long cord, higher occurrence of cord around neck,
cord around body, cord knot, cord prolapse and cord compression.
LONG
SHORT

10. Umbilical artery :-
1.2 + 0.4 mm. at 16 weeks
4.2 + 0.4 mm. at term of gestation.
Umbilical vein :-
2 + 0.6 mm. at 16 weeks.
8.2 + 0.8 mm. at term of gestation.
Progressively increases up to 32 weeks than by a plateau towards
end of pregnancy due to reduction in water content of Wharton’s
jelly .
A significant relationship between umbilical cord diameter and cross
sectional area and foetal biometry.
Wharton’s jelly plays a metabolically active role throughout the
pregnancy.

11. UMBLICAL CORD can be defined as
(A) LEAN CORD
(B) LARGE CORD
(A)LEAN :-If it’s sonographic cross – sectional area is below 10th
percentile for gestational age
LEAN CORD ASSOCIATED WITH
1. Oligohydramnios
2. Foetal distress.
3. SGA Foetus
4. Meconium stained amniotic fluid.
5. Adverse pregnancy outcome.

12. 1. Umbilical cord tumors
2. Urachal cyst
3. umbilical cord mucoid degeneration
4. Omphalomesenteric cyst.
5. Gestational diabetes mellitus.
6. Macrosomia.
LARGE CORD ASSOCIATED WITH
(B) LARGE :- If it’s sonographic cross - sectional area is above 90th
percentile for gestational age.

13. • Colour flow mapping could be used to enhance the definition of
umbilical cord.
• A normal umbilical cord is coiled like a teIephone cord. When the
umbilical cord twisted beyond It is called a hypercoiled umbilical
cord when the cord has too few coils, it is called a hypocoiled
umbilical cord.

14. Sonographic umbilical coiling index is defined as number of vascular
coil in a given cord. Usually 1 coil / 5 cm of umbilical cord length and
may coil as many as 40 times.
< 10th percentile – hypocoiled.
10th – 90th percentile – normocoiled .
>90th percentile – hypercoiled.
Whether an umbilical cord is normal, hypercoiled or hypocoiled is
dependent on the number of coils present in the cord – this is known
as the umbilical coiling index (UCI).
A TYPICAL COILING – Bizarre coiling pattern.

15. Normocoiled
A TYPICAL COILING
Bizarre coiling pattern.

16. Both the hypercoiled and the hypocoiled umbilical cord can result in
the undesirable result of a decrease in the amount of nutrients sent
to the foetus, resulting in intrauterine growth restriction (IUGR) and
increases the risk of foetal death, poor foetal development or a
stillbirth.
Hypercoiled
Hypocoiled

17. Normal placental insertion is central and can be paracentral.

18. Normal umbilical cord insertion
into a laterally implanted placenta.
Normal umbilical cord insertion
into the Posterior placenta

19. Cord Insertion
* Marginal insertion
(Battedore Placenta)
* Furcate insertion
* Velamentous insertion
* Vasa praevia

20. Cord Insertion
ANOMALITIES DEFINITION INCIDENCE SIGNIFICANCE
Furcate insertion Umbilical vessels separate from Rare
cord substance before their insertion
into the placenta
Marginal insertion Battledore placenta 7 % at term Cord being pulled off
cord insertion at the placental during delivery of the
margin placenta
* 2% - 15 %
* associated with preterm labour (?)
* US
Velamentous Umbilical vessels separate in 1.1 % more frequently with
insertion the membranes at a distance twins
from the placental margins. 28% of triples.
Reach surrounded only by a fold
of amnion

22. 1) One or more vessel from cord or placenta cross the cervix
underneath the baby.
2) Vessels unprotected by the Wharton’s jelly in the cord or tissue in
the placenta.
3) Tear on vessel – Life threatening bleeding.
4) Hypoxia if the vessels are compressed between baby & birth canal.
5) Foetal mortality 33 – 100% if not
diagnosed prenatally.
6) Increased risk associated with
a) Velamentous insertion of the cord.
b) Placenta previa.

23. Doppler scan to detect Vasa Previa

24. Physiological herniation of bowel into the base of the umbilical cord
is part of the normal Developmental sequence which occurs at about
the 6th to 8th , and by 8th to 12th mid gut herniates back into the base
of the umbilical cord.

25. Omphalocele is midline abdominal wall defect with herniation of the
abdominal content into the base of the umbilical cord.
U/S FINDINGS:-
Omphalocele looks like a central mass protruding from the anterior
abdominal wall. It varies in size and is covered by a membrane . It
usually contains small intestine and liver. There can be other organs
protruding to the omphalocele such as large intestine, bladder,
stomach, spleen.
Polyhydramnios and ascitis.

26. Colour doppler will be useful for umbilical cord demonstrated.
Omphalocele with stomach entering the omphalocele sac.
23 weeks liver is within the sac and the hepatic vessels
Are demonstrated by colour doppler.

27. * May be found along the course of the cord usually close to foetus (foetal end) or
close to the insertion site.
* TRUE CYSTS :-
> Epithelium lined
> Remnants of the allantois
> Coexist with patent urachus.
* FALSE CYSTS :-
> More common.
> Due to degeneration / Edema of Wharton’s jelly
> Single cyst may resolve completely.
> Multiple cysts may be associated with miscarriage / aneuploidy.
* Difficult / impossible to differentiate true cyst from false cyst.
True Cyst

28. * Cystic lesions within the umbilical cord.
* May be pseudocysts or true umbilical cord.
* Most Umbilical cord cysts disappear by the end of 1st trimester. if they persist beyond
12 weeks or if the cyst are multiple, they associated with a bad prognosis. Certain
Trisomies and foetal anomalies and linked to the presence of umbilical cord cysts.
* The cord cyst must be differentiated from the more echogenic yolk sac which is seen
outside the amnion .
ULTRASOUND IMAGES

29. • This second trimester pregnancy shows evidence of multiple umbilical cord cysts (in
this case, there are two umbilical cord cysts). The colour doppler ultrasound images
show anechoic cystic structures with absence of flow, suggesting umbilical
cord cysts .
• Associated with increased morbidity and mortality for the fetus .
• Higher risk of aneuploidy.
ULTRASOUND IMAGES

31. (Panel A) Transverse view of a normal umbilical cord shows the characteristic
"Mickey mouse" appearance with two arteries (a) and one vein (v) surrounded by
the Wharton's jelly.
(Panel B) Longitudinal view of a three-vessel umbilical cord shows the arteries (a)
looping around the vein (v). Upper panel, conventional two-dimensional ultrasound.

32. Umbilical cord demonstrating 2 arteries of equivalent size and the larger umbilical vein.
Umbilical arterie seen lateral to the bladder.
Colour
doppler
Colour
doppler
Gray
scale

33.  Hyrtl anastomosis is an interarterial anastomosis between the
umbilical arteries, approximately 3 cm from the placental cord
insertion seen in at least 95 % of all placenta.
 The effect of this anastomosis is to equalize pressure between the
placental lobes. If the anastomosis does not equalize the blood flow
between the arteries. Placental will be asymmetric is size.
3D

34. 1. One percentage of single tone and 5% of multiple pregnancies (Twin ,
triplets & more).
2. Left umbilical artery is absent
either
A) Primary agenesis of vessel.
B) Atrophy or atresia of an existing artery.
3. Detected at prenatal sonography by
A) (1) Cross sectional.
(2) Longitudinal image.
B) Lateral to the bladder wall.
SINGLE UMBILICAL ARTERY

35. 4. SUA – Larger may approach the size of umbilical vein usually
greater than 4 mm between 20-36 weeks.
5. Cord should be assessed at multiple level , artery may fuse near
placenta
6. Identification SUA poor :-
1) Oligohydramnios.
2) Small cord size early pregnancy.
3) Multiple pregnancy.
7. Isolated SUA :-
No growth problems of baby.

36. 8. Associated with Chromosomal abnormality
Trisomy 13
Trisomy 18
9 Other tests:-
Aminocenetesis.
Foetal echo.
Post natal assessment required.
10. Associated with velamentous cord insertion.

37. 11) Anomalies associated with
 Musculoskeletal.
 Urogenital
 Cardiovascular
 Gastrointestinal.
 Central Nervous
 Other.

38. Musculoskeletal :-
Cleft lip and palate.
Clubfeet.
Rocker bottom feet.
Polydactyly.
Clino-syndactyly.
Limb reduction defects11.
Vertebral anomalies.
Rib and sternal anomalies.
Urogenital
Renal agenesis.
Renal hypoplasia or dysplasia.
Horseshoe kidneys.
Hydroureter and Hydronephrosis.
Mullerian duct agenesis or anomalies.
Wolffian duct agenesis or anomalies.
Malformed external genitalia.
Cardiovascular VSD.
ASD.
Patent Ductus Arteriosus.
Truncus anomalies.
Valvular anomalies.
Gastrointestinal
Esophageal atresia or stenosis.
T-E fistula.
Imperforate anus.
Gut malrotation.
Omphalocele and gastroschisis.

39. CNS Neural tube defects.
Anencephaly.
Meningomyelocele.
Holoprosencephaly.
Hydrocephalus.
Microcephaly.
Hydrops fetalis.
Other Eye abnormalities
Pulmonary hypoplasia or aplasia.
Laryngeal atresia.
Diaphragmatic hernia.
Cystic hygroma.
Webbed neck.
Hydrops fetalis.

40. Difference in diameter of two umbilical arteries at least 1 mm in three
different places.
Smaller artery - high resistance flow.
Usually benign does not affect the development of the fetus.
Associated with
1) Higher incidence of morphologic placental alteration.
A) placenta bipartite.
B) placenta succenturiata.
2) Absence of hyrtl anastomosis.
3) Anomalous placental insertion-
(marginal, velamentous).

41. Green lines in section a show the tangential course of the arching vessel
with respect to the foetal stomach (*). The left portal vein branch (>) and
ductus venosus ( )are visible. In section b a colour change allows
indentification of the ductus venosus (“ aliasing” caused by flow
acceleration). Caption : hepatic veins (+).
Normal anatomy: intraabdominal course of the Umbilical vein
and union with portal system.

42. U/S Images

43.  RUV Obliterate around 4th week of gestation.
&
 Disappears by the seventh week of gestation.
 Persistent right umbilical vein is a uncommon vascular pathology.
 Left umbilical vein occluded.
 Right umbilical vein persist.
Causes of persistent right umbilical vein
1) First trimester folic acid deficiency
2) Specific Teratogens such as retinoic acid.
3) Early obstruction of the left umbilical vein form external pressure or
occlusion.

44. PRUV in the transverse section.
The criteria used are:
1) portal vein curve towards the Stomach.
2) Foetal gall bladder located medially to the umbilical vein & stomach.
3) Umbilical vein is abnormally connected to right portal vein instead to
the left portal vein.
4) Colour doppler is necessary .
5) Usually detected in 2nd to 3rd trimester.
6) An intrahepatic persistent right umbilical vein may be seen .
7) Abnormally connected to right portal vein and foetal gall bladder is
positioned medial to PRUV.
PRUV can be intra & Extrahepatic.The former is much more commoner.
Ultrasound diagnosis

45. ASSOCIATIONS :- commoner with extrahepatic type.
 Single umbilical artery especially in the extrahepatic type.
 Chromossomal anomalies .
 Triosomy 18
 Noonan syndrome 8.
 Situs anomalies.
 Dextrocardia.
 Congenital cardiac anomalies.
 Congenital renal anomalies.
 Congenital gastrointestinal anomalies
 Vertebral anomalies.

46. Four vessels cords result from the
persistence of the Right umbilical Vein.
(A) TWO VEINS AND TWO ARTERIES
(B) ONE VEIN AND THREE ARTERIES
Persistence of small vitelline arteries.

47. Allantoic or omphalomesenteric duct
remnant is not true vessel.
(C) ONE VEIN, TWO ARTERIES AND DUCT
(D) ARTIFACTS
Exquisite view of the vessels wall and gives
the impression of extra vessels.

48. 5 AND MORE VESSELS CORDS
Numerous variations associated with
conjoined twining.
Cords with unequal numbers of vessels at the foetal end and placental ends
Partial division of the primordial umbilical artery
Fails to divide primordial longitudinally in two umbilical arteries.
division starts at placental end with 3- vessel on the placental end but 2 on
foetal end.

49. a)Ductus venosus agenesis
 Very rare
 The return of the umbilical flow is via various ways
b) Replaced umbilical artery to superior mesenteric artery:-
Left umbilical artery is replaced (which means improperly
connected ) to superior mesenteric artery and right umbilical
artery was in normal position.

50. c) Coronary sinus drainage to the umbilical portion of Left
portal vein.
d) Arteriovenous fistula
ABNORMAL STRUCTURE OR CONFIGURATION OF VESSELS
b)Segmental thinning of umbilical cord vessels
a) Thormbosis a) ARTERY, B) VEIN.

51. c) Umbilical cord constriction
INTRINSIC – ABSENCE OF WHARTON’S JELLY
EXRINSIC :-  Amniotic bands.
 Nuchal loops.
 True knots .
 Fetal grasping.
 Entanglement in monoamniotic twins.
 Cord presentation and occult prolapse

52. NUCHAL CORD :-
1) Cord round the neck.
Two types of cord around foetal neck.
TYPE A- umbilical cord encircles the fetal neck in a sliding manner (less
dangerous)
TYPE B- Nuchal cord encircles the neck in a locking manner (very
dangerous)

53. TYPE A
Nuchal loop 3600 around the foetal neck where the placental end crosses OVER the foetal end
TYPE B
Nuchal loop 3600 around the foetal neck where the placental end crosses UNDER the foetal end.
Type A is loose and can undo itself where as Type B locks and cannot undo itself

54. Disruption of the smooth contour of the foetal neck
compressing skin in that area.

55. Tight cord
ARTERIAL :- Increased velocities and systolic Notch.
VENOUS :- Prestenotic dialatation of vein

56. Umbilical cord abnormalities found in twin gestations are nonspecific and can be
found in singleton gestations ( ie, placenta previa, placental abruption , single
umbilical artery, velamentous cord insertion , vasa previa etc.) However , other
anomalies are unique to twin gestations, and are mainly associated with
monoamniotic twins –these include cord entanglement . most of these conditions can
be diagnosed with ultrasound.

57. * Uncommon, representing only 4 % of malformation of the umbilical cord (1)
* There are types which may / may not be associated with malformation:
1. Intra- abdominal portion of the umbilical vein.
( i.e. intrahepatic or intra – abdominal extrahepatic)
2. Intra- amniotic portion of the umbilical vein.

58. * Cystic round or fusiform shaped mass.
* Orientated in an anteroposterior, caudocranial direction.
* Located within the substance of the liver ( intrahepatic type).
* Located directly cephalad to the insertion of the umbilical vein into the fetal abdomen.
* Differential diagnosis
* Choledochal cyst
* Liver , mesenteric , ovarian or urachal cyst.
* cystic lymphangioma
The demonstration of blood flow within the mass on color doppler differentiates the varix from
the above cystic masses.

59. * Tortuous cystic varix of umbilical vein
* Detection is enhanced by using color doppler imaging.
* Complications
* Cord thrombosis (may be seen in 1 in 25 autopsies in fetuses with cord
abnormalities ) (3)
* Hemorrhage through the amniotic sheath with fetal demise.

60.  Abnormal widening or blood filled buldge.
 Aneurysm is large.
 Can block the blood vessels of umbilical cord.
 Intrauterine growth restriction.
 Excessive bleeding.
 Fetal mortality

61. KNOTS OF THE CORD
* TRUE KNOT :-
When the foetus passes through a loop of the cord. If pulled tight , foetal asphyxia may
result.
* FALSE KNOT:
Localised collection of Wharton’s jelly containing a loop of umblical vessels.
True knot False knot

62. TRUE KNOTS :-
 Incidence 1-2 %
 More common in monoamniotic twins.
 Active foetal movements create true knots.
 Risk of still births is increased 5 to 10 folds in those with true knots.
 FHR Abnormalities are common during labor but cord blood PH Values
are normal.

63. • Although an abnormal or non – reassuring heart tracing can be
indicative of the true knot.
• Method of choice for diagnosis of knot, specifically, four dimensional
,colour doppler & power doppler.
• When a true knot is diagnosed, strict monitoring of foetal well – being
is requied during pregnancy and delivery.
DIAGNOSING TRUE KNOTS:-
True knot

64. (True knot , Hypoxic Ischemic Encephalopathy (HIE)
and cerebral palsy)
1. Long umbilical cord
2. Monoamniotic twin.
3. Polyhydramnios.
4. Mother is carrying twins, triplets or more.
5. Mother more than 35 yrs.
6. Mother smokes or uses drugs.
7. Large for gestational age.
8. Nutritional deficiencies.
INCREASED RISK FACTOR FOR A TRUE KNOT :-

65. PROLAPSE of umbilical cord into endocervical canal at delivery in 0.5 %
cases resulting in perinatal mortality due to cord compression
cord presentation in presence of cord between foetus and internal OS.
Predisposing factors:-
1) Nonvertex foetal lie.
2) Polyhydromnios.
3) Cephalo pelvic disproportion.
4) Multiple gestation.
5) Increased cord length.

66. Hemangioma 
1. Echogenic structure with demonstrable perfusion
2. Common towards placental end
3. Less common – Fetal end of cord
vitelline capillaries.
D/D – Teratoma
Cord haematoma

67. Angiomyxoma 
1. Usually benign .
2. Hetrogenous mass
Teratoma -
1. Usually benign
2. Solid with / without cystic areas
3. Contains tissue from all three germ
cells types.
4. Calcification.

68. Hematoma -  Most after appears hyperechoic but the
echotexture may very depending up on age of haemorrahge.
Spontaneous hematomas are usually due to venous source of bleeding
related to umbilical cord knot’s or torsions
lead to fetal monitoring and possible emergency delivery
involve intrafoetal or extrafoetal portion of umbilical vein

69. Patent urachus is a communication the dome of the bladder and the
umbilicus.
• Also called persistent urachus
• Rare: leads to urination through umbilicus
• May be associated with infections

70. Aneuploidy is the presence of abnormal number of chromosomes in a cell .
whartorn’s jelly in known to influence cell behavior and tissue remodeling
especially during embryogenesis.
Aneuploid foetuses have thicker umbilical cords can be related to increased
amount of wharton’s jelly.
One of the possible cause of increased nuchal translucency in trisomy 21.

71. True and pseudocysts of the cord have similar appearances; true cysts are
usually associated with anomalies of the umbilicus and / or bladder such as
omphalocele or patent urachus.
Higher incidence in reduced number of coiling & absent coiling.
Velamentous insertion.
Short length of cord.
Associated and Tumors & cysts.
Single umblilical artery – Trisomy – 13.
Trisomy - 18.
Persistent right umbilical vein.
Umbilical vein Varix.
Omphalocele
Four & multiple vessels cord

73. NORMAL ABNORMAL

76. Umbilical vein doppler patterns are usually evaluated in the
intra – abdominal portion of the vein.
The appearance of pulsatile flow in the UV is a simple and reliable
marker of circulatory compromise , long recognized as a marker of
asphyxia in small – for gestational age foetus.
(A)umbilical vein (UV).
(B) ductus venosus
(C ) Inferior vena cava (IVC) .

77. (B) Normally has forward blood flow throughout the cardiac cycle. In
compromised fetuses a drop in arterial systolic forward velocities is
observed. As central venous pressure increases, blood flow may be
reversed during arterial systole.
(A) Abnormal UV waveform in haemodynamically compromised fetuses is
characterized by the appearance of pulsations.

78. (C) Abnormal IVC waveforms in intrauterine growth restriction show a
decrease in forward flow during the S-wave (S) and D-wave (D) and
accentuation of reversed flow in the A-wave (annotated ‘a’). As the
condition deteriorates the D-wave may be reversed.

80. The umbilical cord forms between 5th and 12th week of gestation with
contributions from the
1 Body stalk.
2 Omphalomesenteric or vitelline duct.
3 Yolk sac.
4 Allantois.
REFERENCE : RADIOGRAPHICS 1995 ( RSNA 1995)

81.  SINGLE UMBILICAL ARTERY.
 VASA PREVIA.
 VELAMENTOUS INSERTION.
 ABNORMAL UMBILICAL DOPPLER.
 CORD ROUND NECK.
 CORD PROLAPSE.