The Placenta

Question 1

the maternal placenta is the ___ plate

Answer 1

basal

Question 2

flow within the maternal placenta should be ___

Answer 2

low resistance

Question 3

___: functional unit of the placenta

Answer 3

cotyledons

Question 4

blood fills interbillouns spaces to provide nourishment to the fetus through ____

Answer 4

chorionic villi

Question 5

the fetal side of the placenta is the ___ plate

Answer 5

chorionic

Question 6

the chorionic plate is located between where

Answer 6

between the amniotic membrane and the decidua basalis

Question 7

at 12 weeks what is a normal placental thickness measurement

Answer 7

1.5-2cm

Question 8

in the 2nd and 3rd trimester what is a normal placental thickness measurement

Answer 8

<4cm

Question 9

the thickness of the placenta in mm should be equal to the weeks of gestation + ___

Answer 9

10

Question 10

___: hypoechoic area deep tot hat placental that drains the placental tissue

Answer 10

retroplacental complex

Question 11

placental insufficiency is associated with what things

Answer 11

-IUGR
-Pre eclampsia
-smoking
-HTN
poor maternal nutrition
-chronic maternal diabetes prior to pregnancy
-downs
-triploidy

Question 12

an increasing ___ can indicate developing placental insufficiency

Answer 12

increasing S/D ratio

Question 13

placental thinning is defined as placental thickness of ___

Answer 13

<1.5cm

Question 14

placental thinning is associated with what things

Answer 14

• IUGR
• pre eclampsia
• smoking
• maternal HTN
• poor maternal nutrition
• drug/ alcohol abuse

Question 15

placental thickness is defined as placenta measuring ___ in the second trimester and ___ in the third

Answer 15

> 4cm in 2nd trimester and >6cm in 3rd trimester

Question 16

what are some things associated with placental thickening

Answer 16

• twin gestations
• chronic maternal diabetes
• rh incompatibility
• intrauterine infection
• triploidy
• placental insufficiency
• fetal hydrops
• beckwith Wiedemann syndrome

Question 17

___: ectopic pieces of placenta not connected to the main placenta

Answer 17

succenturiate placental lobe

Question 18

S/A grade 0 placenta

Answer 18

• homogeneous
• no calcs
• amniochorionic plate is even throughout

Question 19

S/A grade 1 placenta

Answer 19

• placental body shows few echogenic densities ranging from 2-4mm
• chorionic plate shows small indentations

Question 20

S/A grade 2 placenta

Answer 20

• chorionic plate shows marked indentations

- echogenic densities within the placenta increase in side and number

Question 21

S/A grade 3 placenta

Answer 21

• complete indentations of chorionic plate through basilar plate
• numerous calcs

Question 22

___: membranous chorion does not extend to the edge of the placenta

Answer 22

extrachorial placenta

Question 23

___: more central attachment of the membranes without a central ring of folded amnion and chorion

Answer 23

circummarginate placenta

Question 24

___: smaller chorionic ring surrounded by folds of thickened amnion and chorion

Answer 24

circumvallate placenta

Question 25

circumvallate placenta has an increased risk of what

Answer 25

abruption or spontaneous abortion

Question 26

___: pooling of maternal blood in the subchorionic space

Answer 26

fibrin deposition

Question 27

___: ischemia of placental villi

Answer 27

placental infarcts

Question 28

what can cause placental infarcts

Answer 28

obstructed maternal blood flow into intervillous space

Question 29

S/A placental infarct

Answer 29

- triangular shaped - anechoic with base of triangle touching the maternal side of the placenta - does not demonstrate internal blood flow on color

Question 30

___: enlarged spaces in the placenta filled with blood

Answer 30

placental lakes

Question 31

S/A placental lake

Answer 31

- nearly anechoic | - slow swirling of blood may be seen

Question 32

multiple placental lakes seen early on in the pregnancy has been associated with what

Answer 32

decreased umbilical artery flow and IUGR

Question 33

___: large thrombus within the subchorionic venous system due to obstructed venous flow

Answer 33

breus mole

Question 34

___: placental crosses the internal os of the birth canal

Answer 34

placental previa

Question 35

what are some risk factors for placenta previa

Answer 35

- AMA - smoking - multiple gestations - prior uterine surgery

Question 36

what is the most common symptom of placental prevue

Answer 36

painless 3rd trimester bleeding

Question 37

what are the different types of previas

Answer 37

- complete - partial - marginal - low lying - vasa previa

Question 38

which type of previa completely covers the internal os

Answer 38

complete previa

Question 39

which type of previa partially covers the os

Answer 39

partial

Question 40

which type of previa touches the edge of the os

Answer 40

marginal

Question 41

which type of previa is within 2cm of the os

Answer 41

low lying

Question 42

which type of previa does the placental vessels cover the os

Answer 42

vasa

Question 43

___: abnormal implantation of placental tissue

Answer 43

morbidly adherent placenta

Question 44

who is at risk for morbidly adherent placenta

Answer 44

- history of grand multiparty - history of placental previa - prior c section

Question 45

which type of abnormal placental tissue implantation invades less than 50% of the way through the myometrium

Answer 45

placental accrete

Question 46

which type of abnormal placental tissue implantation invades more than 50% of the way through the myometrium

Answer 46

placental increta

Question 47

which type of abnormal placental tissue implantation extends through the uterine wall to the bladder and adjacent pelvic structures

Answer 47

placental percreta

Question 48

___: early separation of placental from the uterine wall

Answer 48

placental abruption

Question 49

what are some risk factors for placental abruption

Answer 49

- short umbilical cord - DM - HTN - SMoking - pre eclampsia - IVC compression - AMA - fibroids - multiparity

Question 50

S/S placental abruption

Answer 50

- severe bleeding - pain - uterine spasms - signs of shock

Question 51

S/A placental abruption

Answer 51

-hematomas/ fluid collections seen in retroplacental space

Question 52

what is the most common benign mass of the placenta

Answer 52

chorioangioma

Question 53

what labs would be elevated with chorioangiomyoma

Answer 53

MSAFP

Question 54

S/A chorioangioma

Answer 54

- highly vascular - hypoechoic mass - usually adjacent to cord insertion

Question 55

marginal cord insertion is also called ____

Answer 55

battledore placenta

Question 56

which type of cord insertion attaches to the placental periphery <2cm from the edge

Answer 56

marginal

Question 57

which type of cord insertion does the cord attach to the placental membranes

Answer 57

velamentous

Question 58

which type of cord insertion can be seen with vasa previa

Answer 58

velamentous

Question 59

velamentous cord insertion can lead to what

Answer 59

- abruption | - fetal death is PROM

Question 60

velementous cord insertion is associated with what

Answer 60

- IUGR - preterm birth - congenital defects

Question 61

what is the most common umbilical cord anomaly

Answer 61

2 vessel cord

Question 62

placental previa is more commonly caused by what

Answer 62

low implantation of the embryo