Placenta Flashcards Preview

OB/GYN > Placenta > Flashcards

Flashcards in Placenta Deck (37)
0

What is the earliest the placenta is seen on US

Week 12

1

Placenta

Vascular organ
Discoid shape
Weighs 500-600 g

Chorionic plate on fetal side
20 lobes
Basilar plate on maternal side adj to retroplacental complex

2

Major functioning unit of placenta

Chorionic Villi

3

Functions

Protection, nutrition, respiration, excretion

4

Cord should insert

Centrally

5

May ID by 8-10 wks as

Focal thickening

6

Size

< or = 5 cm

7

Visualize retroplacental complex by

18 wks

8

Grading

0: smooth no Ca+, homo
1: sm Ca+ randomly dispersed
2: Ca+ of basilar plate
3: Ca+ intentions of pl extending from chorionic plate to basilar plate. See lobes.

9

Grade 3 < 34 wks inc risk for

IUGR, preeclampsia

10

Grade/calcification delay with, accelerated with

Maternal diabetes, Rh blood

HTN, IUGR, smoking, AMA

11

Bilobate placenta

2 lobes both equal in size. Cord inserts between both lobes.

12

Succentureate Lobe/Accessory Lobe

1 or more small lobes connect to main placenta. If retained after delivery, may hemorrhage. Connecting vessels may overly internal os.

13

Annular placenta

Doughnut, ring shape

14

Placenta membranacea

Covers surface of sac, very thin.

Placenta Diffusa: rare, covers most of uterine wall.

15

Circumvallate placenta

Placenta extends beyond chorionic plate. Curled up margins.

Assoc with bleeding and preterm.

16

Synechiae

Amniotic sheets/folds, thick band with color flow

17

Amniotic band syndrome/ ADAM complex

Rare, thin membrane of amnion freely cross sac. May entangle fetus. Risk of ABS with early amniocentesis

18

Placenta size increase with

Diabetes, Rh, CMV, chorioangioma, abruption, twins, hydrops, fetal anemia, triploidy, maternal anemia

19

Placental size decrease

IUGR, preeclampsia, infarction, toxemia, maternal cardio renal disease, trisomies, severe diabetes, chronic infection, htn

20

Placenta Previa

Placental covers internal os

Complete/Total: covers both sides of cx canal
Partial/Marginal
Low lying: within 2 cm of io

Do c section

Painless vag bleeding

Inc with AMA, smoking, multiparity, c sections, low ut scars, trauma, hx D&C, twins, abnl fetal lie

Premature delivery, maternal hemorrhage, placenta accreta, post partum hemorrhage, IUGR,

Over distended bladder cause false positive

21

Trophotropism

Hypertrophy of upper part & atrophy of lower part bc LUS isn't as vascular

22

Vasa Previa

Vessels overly internal os. High fetal mortality. C section.

23

Abruption

Premature placenta detachment
Dangerous.

Knife like pain. Bleeding, shock, preterm labor, fetal distress/demise

Assoc with HTN, cocaine, vasc disease, trauma, preeclampsia, short umb cord, fibroids, previa

Hematoma. Retroplacental hemorrhage

24

Placenta Accreta

Abnl placental attachment

Accreta: on myometrium, mildest, most common
Percreta: into myometrium
Increta: through serosa, rarest

Hx of c section + previa = 25% chance

25

Chorioangioma

MC placental tumor

1%, benign vasc tumor, inc MSAFP, through fetal surface of placenta, solid, complex, usually near cord insert.

Large leads to hydrops, polyhydramnios, hemorrhage, premie, IUGR, demise, cardiomegaly

26

Teratoma

Rare, usually benign, malignant very bad, complex mass with shadow.

27

Mets to placenta

From mom: Melanoma, Breast cancer, lung cancer. Lung most common.

Fetal: neuroblastoma, leukemia

28

Umbilical cord

2 arteries, 1 vein. Mickey Mouse, surrounded by Wharton's Jelly for protection.

Length: 55cm at term.
Should insert centrally

29

Marginal cord insertion / battledore placenta

Inserts within 2 cm of edge of placenta. (Inside placenta)

30

Velamentous insertion

Cord inserts a distance away from placenta (cord inserts on membrane)

31

Knotted cord

Difficult to ID, hazardous if construction occurs.

32

Nuchal Cord

Cord around fetal neck, 20% of deliveries. Nurse unwraps cord when delivering.

33

Cord prolapse

Part of cord presents before fetus. May compromise circulation. Dangerous at birth.

34

Single Umbilical Artery / 2 Vessel Cord

1 artery at bladder. Mickey Mouse missing ear trvs.
Inc risk IUGR, tri 18, 13, 21

35

Hemangioma

Benign vascular hyperechoic umbilical cord mass

36

Teratoma

Ca+. Umbilical cord teratoma.