placenta

battledore placenta

Cord insertion into the margin of the placenta

basal plate

Maternal surface of the placenta that lies contiguous with the decidua basalis

chorionic plate

Part of the chorionic membrane that covers the placenta

placenta previa

Placenta grows in the lower uterine segment and covers all or part of the cervix

chorionic villi

Microscopic vascular projections from the chorion that combine with maternal uterine tissue to form the placenta

decidua basalis

Part of the decidua that unites with the chorion to form the placenta

decidua capsularis

Part of the decidua that surrounds the chorionic sac

chorion frondosum

Portion of the chorion that develops into the fetal portion of the placenta

Circum-marginate placenta

Placental condition in which the chorionic plate is smaller than the basal plate, with a flat interface between the fetal membranes and the placenta

circumvallate placenta

Placental condition in which the chorionic plate is smaller than the basal plate; the margin is raised with a rolled edge

placenta accreta

Growth of the chorionic villi superficially to the myometrium; does not penetrate through the myometrium

lower uterine segment (LUS)

Lower part of the uterine cavity, which expands during pregnancy and joins with the cervical canal

placenta percreta

Growth of the chorionic villi through the myometrium to the uterine serosa

Braxton Hicks contractions

Spontaneous painless uterine contractions that occur throughout a pregnancy

placental migration

The placenta is attached to the uterine wall; as the uterus enlarges, the placenta “moves” with it. Therefore a low-lying placenta may move out of the uterine segment in the second trimester.

Wharton’s jelly

Mucoid connective tissue that surrounds the vessels within the umbilical cord

vasa previa

Occurs when the intramembranous vessels course across the internal cervical os

placenta increta

Growth of the chorionic villi deep into the myometrium

ligamentum venosum

Fibrous remains of the ductus venosus from fetal circulation

molar pregnancy

Also known as gestational trophoblastic disease; abnormal proliferation of trophoblastic cells in the first trimester

abruptio placentae

Premature detachment of the placenta from the maternal wall

ductus venosus

Connection that is patent during fetal life from the left portal vein to the systemic veins (inferior vena cava)

succenturiate placenta

One or more accessory lobes connected to the body of the placenta by blood vessels

single umbilical artery

High association of congenital anomalies with this

hemangioma of the cord

Vascular tumor within the umbilical cord

ductus venosus

The smaller, shorter, and posterior of the two branches into which the umbilical vein divides after entering the abdomen. It empties into the inferior vena cava

true knots of the umbilical cord

Arise from fetal movements and are more likely to develop during early pregnancy, when relatively more amniotic fluid is present; associated with advanced maternal age, multiparity, and long umbilical cords

omphalomesenteric cyst

Cystic lesion of the umbilical cord

superior vesical arteries

After birth, the umbilical arteries are known as these

allantoic duct

Elongated duct that contributes to development of the umbilical cord and placenta during the first trimester

omphalocele

Failure of the bowel, stomach, and liver to return to the abdominal cavity; completely covered by a peritoneal-amniotic membrane

vasa previa

Occurs when the umbilical cord vessels cross the internal os of the cervix

membranous (velamentous) insertion of the cord

Cord inserts into the membranes before it enters the placenta

nuchal cord

Occurs when the cord is wrapped around the fetal neck

gastroschisis

Anomaly in which part of the bowel remains outside the abdominal wall without a membrane

umbilical herniation

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

false knots of the umbilical cord

Occurs when blood vessels are longer than the cord; they fold on themselves and produce nodulations on the surface of the cord

spiral artery

delivers oxygenated blood into placenta

spiral vein

removes deoxygenated blood from placenta

cotyledon

15-20 in placenta

major functional unit in placenta

chorionic villis

mature placenta weight

450-550 grams

mature placenta length

16-20 cm

placenta thickness in AP

2-5cm

most common placental position

posterior

grade 0

regular, smooth placenta

grade 1

small intraplacental calicifications

grade 2

calcification - basilar plate

commas on chorionic side

grade 3

calcification indentation

echo spared or fallout areas

irregular densities with acoustic shadowing

AMA

advanced maternal age

35 or older

complete previa aka

placental previa

associated with oligohydramnios, IUGR, cerebrospinal injury

placental infarction

umbilical cord

one vein and two arteries

moth like appearance

placenta increta

best way to diagnose accreta spectrum

MRI

most dangerous form of placenta accreta

placenta percreta

not protected by Wharton’s Jelly

velamentous insertion

vasa previa results in…

c-section

AFI should be between

5-24 cm

AFI <5cm

oligohydramnios

AFI >24 cm

polyhydramnios

maximum vertical pocket

measures the depth of the largest visible pocket of fluid

normal range of maximum vertical pocket in singleton

2-8 cm

normal range of maximum vertical pocket in twin gestation

2-7 cm

non-stress test

evaluates changes in fetal heart rate with fetal motion