The Umbilical Cord

Gastroschisis is characterized by

NO overlying sac or peritoneum covering the abdominal wall contents and them freely protruding

What is another name for membranous insertion of the cord?

Velamentous insertion of the cord

The umbilical cord is surrounded by gelatinous stroma called

Whartons jelly

Gastroschisis involves ___ layers of the abdominal wall and measures ______

all, 2-4 cm

The _______ vessels become the umbilical vessels

allantoic

With marginal insertion of the cord (battledore placenta) the cord implants into the

edge of placenta instead if the middle

Hematoma of the cord may be caused by trauma which results in

extravasation of blood into Wharton's Jelly

Umbilical herniation is when the intestines return normally to the abdominal cavity and then herniate PREnatally or POSTnatally due to

failure of anterior abdominal wall to close completely at the level of umbilicus

The umbilical arteries arise from the fetal ______ and course alongside the ______

iliac arteries, fetal bladder

Focal dilatation of the umbilical veins is almost always ___________ but _____ in location

intra-abdominal, extra hepatic

Umbilical cord stricture is uncommon but distinctive condition associated with

intrauterine fetal death

US detection of SUA should prompt

investigation of further fetal anomalies

The arteries are spiral with the ______

larger umbilical vein

On US the umbilical vein curves toward the ________ rather than toward the liver

left sided stomach

The ____ umbilical artery is absent more often than the _____ umbilical artery

left, right

After birth, the ductus venosus transforms into the

lig. venosum (2nd week after birth)

Coiling of the cord is ____ and related to ______

normal, fetal activity

What is the most common cord entanglement in fetuses?

nuchal cord

Thrombosis of the umbilical vessels is defined as

occlusion of one or more vessels of umbilical cord

The umbilical cord forms as a fusion of the ___________ ______ _____ and ______ ______

omphalomesenteric yolk stalk, allantoic stalk

The umbilical cord in an essential link for _____ and ______ among the fetus, placenta and mother

oxygen, nutrients

The umbilical vein transports _____ blood TO the _______ from the _______

oxygenated, fetus, placenta

The ductus venosus forms the conduit between the ________ and the _________

portal system, systemic veins

Vasa previa is defined as the

presence of umbilical cord vessels crossing the internal os of cervix

Persistence of __________ rather than normal __________ is called _______

right portal vein, left-sided portal vein, intrahepatic right portal vein

Fetus with a _____ twist in the cord has a higher incidence of fetal anomalies than one with a _____ twist

right, left

The intra-abdominal portion degenerates after birth and becomes the

round ligament of liver (lig. of teres hepatis)

The cord length in twins is ____ than in singletons

shorter

Umbilical cord stricture results in

stillborn

With SUA, in the long axis view, the two vessel cord appears

straight and non coiled

The yolk stalk is the umbilical duct connecting the _____ with the _____

yolk sac, embryo

Thrombosis of the umbilical vessels primarily occurs in the ____

umbilical vein

Cord insertion into the _______ abdominal wall is an important landmark

ventral

______ is most frequently involved in hematoma of the cord

Umbilical vein

The length of the umbilical cord is determined by what two things?

-amount of amniotic fluid present in the 1st and 2nd trimesters -fetal mobility

True knots are associated with

-long cords -polyhydramnios -IUGR -monoamniotic twins

The amniotic membrane covers

1) the fetal surface of placenta 2) the multiple vessels that branch from the umbilical arteries

What two factors contribute to the failure of fetus to fill pelvic inlet cavity?

1. small presenting part 2. increased frequency of abnormal presentation in premature labor

After ____ weeks gestation, amniotic fluid volume increases rapidly due to _____

10, fetal voiding

The normal diameter of the cord is up to ___

2 cm

There are ____ arteries and ___ vein in the umbilical cord

2, 1

Short umbilical cords LESS than _____ are associated with _____

35 cm, oligohydramnios

The normal cord measures _______ in length

40-60 cm

The umbilical cord forms during the first ____ weeks gestation or ____ menstrual weeks

5, 7

Intestines grow at faster rate that the abdomen, therefore they herniate at ___ weeks and remain there until _____ weeks

7, 10

Long umbilical cords GREATER than _____ are associated with _______

80 cm, polyhydramnios

The umbilical cord can be visualized by the ____ week until term

8th

________ and ______ are FOCAL dilations of umbilical vessels affecting the umbilical artery and vein

Aneurysm, varix

Prolapse of the umbilical cord occurs when the cord lies

BELOW the presenting part

What is another name for marginal insertion of the cord?

Battledore Placenta

__________ is useful for recording absence of blood flow within umbilical cord

Color Doppler

___________ and cord length are roughly equivalent during the 1st trimester

Crown Rump Length

A probable cause for single umbilical artery (SUA) is ______ of one of the umbilical arteries in early development

atrophy

Fetal mortality is high in the premature population secondary to _______ and _____

birth trauma, anoxia

Falso knots of the umbilical cord are seen when

blood vessels are longer than cord (kinking of vessels to accommodate to length of cord)

The umbilical cord should normally insert into the______ of the placenta

center

The umbilical vein is formed by the confluence of the __________

chorionic veins of the placenta

Ompahlocele is characterized by the

complete covering of the intestines by a peritoneal amniotic membrane

________ of the cord reduces or cuts off blood supply to the fetus and may result in fetal demise

compression

The presence of more than three vessels in the cord has been documented with

conjoined twins

Wharton's jelly is an important structure to recognize when performing __________

cordocentesis

Omphalomesenteric cyst

cystic lesion of the umbilical cord caused by persistence and dilatation of segment of omphalomesenteric duct

The absence of cord twisting is an indirect sign of

decreased fetal movement

The paired umbilical arteries carry ______ blood from the _____ to the _____

deoxygenated , fetus, placenta

True knots of the umbilical cord arise from

fetal movements and are more likely in early pregnancy (also from venous stasis and thrombosis)

All pregnancies with single umbilical artery has a transverse umbilical artery diameter _____

greater than 4 mm

The sites of origin for hemangioma of cord are the

main vessels of umbilical cord, usually arises from um. artery

With membranous (velamentous) insertion of the cord, the cord inserts into the

membranes before it enters the placenta rather than inserting directly into placenta

Omphalocele is a type of umbilical cord mass that results from

the failure of intestines, liver and other organs to return to the abdominal cavity