Ch. 22- Abnormalities of the Placenta and Umbilical Cord

Focal dilatation of an artery

aneurysm

Placenta where then lobes are nearly equal in size and the cord inserts into the chorionic bridge of tissue that connects the two lobes

bilobed placenta

• succenturiate is an accessory lobe

Fatal condition associated with multiple congenital anomalies and absence of the umbilical cord

body stalk anomaly

Very rare condition where there is massive subchorionc thrombosis of the placenta secondary to extreme venous obstruction

Breus mole

Attachment of the placental membranes to the fetal surface of the placenta rather than to the underlying villous placental margin

extrachorial placenta

Bending, twisting, and bulging of the umblical cord vessels mimicking a knot in the umbilical cord

false knot

Periumbilical abdominal wall defect, typically to the right of normal cord insertion that allows for free-floating bowel in the amniotic fluid

gastroschisis

Condition characterized by multiple complex fetal anomalies and a short umbilical cord

limb-body wall complex

Occurs when the umbilical cord inserts at the placental margin

marginal insertion or battledore placenta

Central anterior abdominal wall defect at the site of cord insertion into the fetal abdomen that results in abdominal organ protruding outside the abdominal cavity but contained by a covering membrane consisting of peritoneum, Wharton jelly, and amnion

omphalocele

Term that refers to a thickened or hydropic placenta

placentomegaly

Linear, extra amniotic tissue that projects into the amniotic cavity with no restriction of fetal movement

synechiae (amniotic sheets)

• causes no harm to fetus as opposed to amniotic bands

Intraplacental area of hemorrhage and clot

thrombosis

Result of fetus passing through a loop or loops of umbilical cord creating or more knots in the cord

true knot

Failure of the normal physiologic gut herniation to regress into the abdomen, resulting in a small amount of bowel protruding into the base of the umbilical cord

umbilical hernia

Vascular structure connecting the fetus and placenta that normally contains two arteries and one vein surrounded by Wharton jelly

umbilical cord

Method of assessing the degree of umbilical cord coiling, defined as the number of complete coils per centimeter length of cord

umbilical coiling index (UCI)

Tubular, anechoic structures found beneath the chorionic plate that correspond to blood-filled spaces found at delivery

venous lakes

Placental hydrops produces a:

• thin placenta with venous lakes

• thick placenta with a “ground glass appearance”

• annular placenta with irregular contour

• membranacea placenta with low resistance blood flow

thick placenta with a “ground glass appearance”

A “jelly like placenta” is associated with:

• venous lakes

• IUGR

• adjacent fibroids

• degeneration

IUGR

A succenturiate placenta:

• has increased frequency in primigravidas

• is ring shaped

• most often have velamentous umbilical cord insertion

• is edematous

most often have velamentous umbilical cord insertion

Circumvallate placental tissue is:

• flat and noted on approximately 20% of placentas

• associated with a thickened rolled chorioamniotic membrane

• extremely rare, 1:20,000 to 40,000 pregnancies

• prone to fetal macrosomia

associated with a thickened rolled chorioamniotic membrane

Risk factors for placenta previa include all except:

• previous C-section

• multiple gestations

• previous elective abortions

• hypertension

hypertension

A placenta is considered low-lying if the inferior margin is:

• 0.5 cm from the internal os

• adjacent to the internal os

• within 2 cm of the internal os

• posterior

within 2 cm of the internal os

The most infiltrative form of placenta accreta is:

• percreta

• accreta

• increta

• invasive

percreta

Attachment problems of the placenta are known as all except:

• morbidly adherent placenta

• placental attachment disorder

• abnormally invasive placenta

• infiltrative myometrial placenta

infiltrative myometrial placenta

Placental infarction (necrosis) is:

• visualized at the fetal placental surface

• owing to obstructed spiral arteries

• multiple hemorrhages into placental lakes

• a factor in macrosomia

owing to obstructed spiral arteries

A benign vascular malformation of the placenta is a:

• teratoma

• septal cyst

• lacunae

• chorioangioma

chorioangioma

Premature separation of all or part of the placenta from the myometrium is:

• hemorrhage

• subchorionic

• abruption

• subdural

abruption

Linear, extra amniotic tissue projecting into the amniotic cavity is noted often in pregnant women with a history of:

• uterine curettage

• cervical dilation

• multiples

• STDs

uterine curettage

Amniotic band syndrome is a condition that:

• involves free-floating membrane

• is a result of rupture of the amnion without rupture of the chorion

• is not revealed in the third trimester

• involves the uterine septum

is a result of rupture of the amnion without rupture of the chorion

• causes abnormalities but amniotic sheets don’t

A condition of pregnancy where the trophoblastic cells produce excessive amounts of beta-hCG is:

• multiparity

• fetal entrapment

• molar pregnancy (hydatidiform mole)

• compression syndrome

molar pregnancy (hydatidiform mole)

SUA (single umbilical artery) is associated with all except:

• cardiovascular malformations

• central nervous system defects

• musculoskeletal abnormalities

• skeletal dysplasia

skeletal dysplasia

PRUV, a common vascular variant, describes:

• a strictured right portal vein

• a duplicated right portal vein

• pancreatic right portal vein

• open right portal vein

open right portal vein

• PRUV: persistent right umbilical vein

TTTS (twin-to-twin transfusion syndrome) is caused by:

• battledore umbilical insertion

• monochorionic twin pregnancies sharing a placenta with anastomoses between the umbilical vessels

• oligohydramnios

• discordant fetal size and pollyhydramnios

monochorionic twin pregnancies sharing a placenta with anastomoses between the umbilical vessels

Prenatal management of known umbilical pseudo and true cysts:

• is not necessary because resolution is imminent

• typically refers to MRI for evaluation

• involve serial US examinations

• displays echogenic characteristics near the placental insertion

typically refers to MRI for evaluation

Cord prolapse is defined as:

• a compressed umbilical cord

• presentation of the umbilical cord in advance of the fetal presenting part during labor and delivery

• excessive bending and twisting of the umbilical cord

• focal bulge or vascular protuberance of the umbilical cord

presentation of the umbilical cord in advance of the fetal presenting part during labor and delivery

Subamniotic cysts or subamniotic hematomas result form rupture of ___________ (________) _________ close to the umbilical cord insertion into the placenta.

chorionic (fetal) vessels

Selective loss of placental parts and growth of other parts is known as ______________ ________________.

trophoblastic trophotropism

The ring shaped annular placenta is related to postpartum ____________ mostly owing to poor separation.

hemorrhage

Acute placental abruption hemorrhage appears highly ____________ on ultrasound.

echogenic

Choriocarcinomas appear as _____________, echogenic, and _______________ masses.

heterogenous; hypervascular

Placenta accrete is mostly located in the ___________, _________ uterine segment.

anterior, lower

Visualization of multiple ___________ are highly suggestive of placenta acreta.

lacunae

Multiple chorioangiomas or those larger than ___ cm are related to maternal and fetal complications.

5

Early detection of fetal anemia is possible where chorioangioma is suspected, through Doppler measurements of the _________ ____________ ________ (MCA).

middle cerebral artery

Extremely hydropic and swollen chorionic villi are frequently related to ____________ ______ (molar pregnancy).

hydatidiform mole

Molar pregnancies have a characteristic ____________ appearance with uterine cavity ____________.

snowstorm; distention

The most common reason for emergency postpartum hysterectomy is a morbidly __________ placenta.

adherent

A coexisting fetus with an enlarged thickened placenta revealing multiple small cystic spaces is a _________ hydatidiform mole.

partial

The placenta may sonographically appear thickened in some cases of IUGR, with patchy areas of _________________ and abnormal texture.

hypoechogenicity

A two-vessel umbilical cord reveals the presence of a single umbilical ___________ and is sometimes associated with congenital anomalies such as cardiovascular malformations, central nervous system defects, _____ or genitourinary defects, and ________ malformations.

artery; GI; MSKLTL

The umbilical vessel abnormality seen with conjoined twins is __________________ vessels.

supernumerary

Maternal cocaine abuse leads to the fatal condition ______ _______ __________.

body stalk anomaly

Velamentous insertion is more frequent in ___________ gestations.

multiple

Compressed umbilical cords place the fetus at risk for _______ ________ or ____________ compromise.

fetal hypoxia or circulatory

A successful method of identifying a nuchal cord is imaging using _______ ________ technology.

color Doppler

Which of the following is described as the focal dilation of the abdominal portion of the umbilical vein?

• allantoic cyst

• umbilical cord varix

• umbilical cord aneurysm

• umbilical cord berry

umbilical cord varix

An anechoic mass is noted within the umbilical cord during a routine sonographic examination. What is the most likely diagnosis?

• hemangioma

• vasa previa

• chorioangioma

• allantoic cyst

allantoic cyst

All of the following are associated with a thin placenta except:

• preeclampsia

• IUGR

• fetal hydrops

• long-standing diabetes

fetal hydrops

All of the following are associated with a thick placenta except:

• fetal infections

• Rh isoimmunization

• placental insufficiency

• multiple gestations

placental insufficiency

Placenta accreta denotes:

• the abnormal attachment of the placenta to the myometrium

• the premature separation of the placenta from the uterine wall

• the invasion of the placenta into the myometrium

• the condition of having the metal vessels rest over the internal os

the abnormal attachment of the placenta to the myometrium

Doppler sonography reveals vascular structures coursing over the internal os of the cervix. This finding is indicative of:

• vasa previa

• placenta previa

• placenta increta

• abruptio placentae

vasa previa

All of the following are clinical features of placental abruption except:

• vaginal bleeding

• uterine tenderness

• abdominal pain

• funneling of the cervix

funneling of the cervix

The most common placental tumor is the:

• choriocarcinoma

• maternal lake

• chorioangioma

• allantoic cyst

chorioangioma

What is the most common cause for an emergency postpartum hysterectomy?

• morbidly adherent placenta

• body stalk anomaly

• placenta percrete

• incomplete abortion

morbidly adherent placenta

• placenta accreta, increta, and percreta