Placental and Gestational Disorders

Question 1

Placenta: Functions (3)

Answer 1

1. establish effective communication between mother and the developing fetus while maintaining the immune and genetic integrity of both individuals;
2. allows intimate apposition of maternal and fetal circulations for exchange of nutrients, oxygen, and waste products;
3. secretes a variety of hormones including human chorionic gonadotropin (hCG)

Question 2

Define

1. Amnion
2. Chorion
3. What does the chorion attach to?
4. Define Chorionic Villi

Answer 2

1. inner layer of the membrane surrounding the developing fetus, forms the amniotic cavity
2. outer layer of the surrounding the developing fetus, forms the amniotic cavity
3. decidua (endometrium of pregnancy)
4. Placenta composed of chorionic villi that sprout from the chorion to provide a large contact are between the fetal and maternal circulations

Question 3

Chorionic Villi

1. Histo look
2. What are the two layers of epithelium?

Answer 3

1. central stroma, w/ vascularity

2. syncytiotrophoblast, cytotrophoblast

Question 4

Fetal Circulation

1. Under normal circumstances, when do the maternal and fetal blood mix?
2. What are the umbilical vessels?
3. How does maternal blood move?

Answer 4

1. never
2. 1 vein (carries oxygenated blood to baby), 2 arteries (carries deoxygenated blood back to receive oxygen and nutrients
3. enters placenta via endometrial arteries and leaves via endometrial veins

Question 5

Spontaneous Abortion (Miscarriage)

1. When does it usually occur?
2. How often does it occur?
3. What are more than half due to?
4. What are some other causes?

Answer 5

1. pregnancy loss before 20 weeks
2. 1/3 of all pregnancies are lost (10-15% of recognized pregnancies)
3. chromosomal abnormalities (tri/monosomy)
4. Defective implantation, fetal abnormalities, maternal causes (inflammation, uterine deformity, DM, luteal-phase defects) unknown

Question 6

Ectopic Pregnancy

1. Define
2. How often does it occur?
3. Where?
4. Predisposing Factors
5. Presentation
6. Complications

Answer 6

1. implantation occurs outside uterus
2. 1:150 pregnancies
3. 90% fallopian tubes, 10% ovary/abdom. cavity; may also implant in corn (horn) of uterus
4. inflammation and scarring (pelvic inflamm disease –> constrictions and fibrosis of fallopian tube); intrauterine devices can increase risk
5. abdominal pain, acute abdomen
6. rupture and hemorrhage (esp of fallopian tube)

Question 7

Twin Placentas

1. 3 types of twin placentas
2. What implies monozygotes?
3. What determines the number of amnions?

Answer 7

1. diamnionic, dichorionic; diamnionic, monochorionic; monoamnionic, monochorionic;
2. monochorionic placenta; however, dichorionic can also be identical twins
3. time of splitting of ovum

Question 8

When does to ovum split to create:

1. dichorionic, diamnionic placenta?
2. monochorionic, diamnionic placenta?
3. Monochorionic monoamnionic placenta?

Answer 8

1. day 0-4
2. day 4-8
3. day 8-12

Question 9

Twin-Twin Transfusion

1. What happens?
2. What happens to each twin?

Answer 9

1. 1 fetus gets more blood than the other

2. the less perfused twin often does not survive; well perfused twin may not make it as well

Question 10

Placenta Previa

1. Define
2. Symptom
3. how is baby delivered?
4. Risk factor?

Answer 10

1. attachment of placenta to lower uterine segment or cervix
2. painless, serious 3rd trimester bleeding due to dilatation of cervix;
3. C-section
4. previous C-sections

Question 11

Placenta Accreta

1. Define
2. Causes what?
3. What can it do?
4. Predisposing factors

Answer 11

1. partial or complete absence of decidua with adherence of placental villous tissue directly to myometrium (failure of placental separation)
2. post-partum bleeding
3. Can invade into other structures, like the bladder
4. Placenta Previa, previous C-section (scarring of endometrium)

Question 12

Abruptio Placentae

1. Define
2. What forms?
3. What happens to the fetus?
4. What happens to the mother?

Answer 12

1. premature separation of the placenta prior to delivery
2. retroplacental blood clot
3. blood supply of O2 and nutrients to the fetus is compromised to a greater degree with increasing size of the abruption; potential fetal death
4. painful bleeding, hemorrhage

Question 13

Retained Placental Tissue

1. Define
2. May cause what?

Answer 13

1. retention of tissue after spontaneous miscarriage or elective abortion
2. post-partum hemorrhage, infection,

Question 14

Preeclampsia- Eclampsia

1. Define
2. Can also cause…
3. Who gets it? When?
4. Which pregnancy is it most common in?

Answer 14

1. systemic syndrome characterized by widespread maternal endothelial dysfunction presenting clinically with hypertension, edema, and proteinuria during pregnancy
2. fetus problems due to insufficient blood supply to developing fetus
3. 3-5% of pregnancies; 3rd trimester;
4. 1st pregnancy, those w/ underlying HTN or diabetes

Question 15

Preeclampsia- Eclampsia: Pathogenesis

1. How do we know that the placenta plays a role in symptoms?
2. Theories of pathogenesis (3)

Answer 15

1. symptoms disappear after delivery of placenta
2. abnormal placental vasculature;
   endothelial dysfunction and imbalance of angiogenic and anti-angiogenic factors (more anti-angiogenic factors);
   Coagulation abnormalities (imbalance btwn thromboxane and prostacyclin- abnormally high thromboxane)

Question 16

Preeclampsia- Eclampsia

1. What happens to spiral arteries?

Answer 16

1. They fail to remodel; usually, the musculature around them regresses allowing them to be high capacitance vessels;
   when this fails to occur, blood vessels can’t carry as much blood to the fetus

Question 17

Preeclampsia- Eclampsia: How are the following organs involved?

1. Liver
2. Kidney
3. Brain
4. Other organs involved

Answer 17

1. fibrin thrombi, hemorrhage, necrosis
2. fibrin in glomeruli and capillaries, renal cortical necrosis
3. hemorrhage and thrombosis
4. heart and anterior pituitary

Question 18

Placenta Morphology in Preeclampsia- Eclampsia

1. What happens to placenta?
2. What does that cause?

Answer 18

1. Malperfusion, ischemia, vascular injury
2. –> infarcts, retroplacental hematoma, villous ischemia, acute therosis of uterine vessels (fibrinoid necrosis, macrophages, inflammation)

Question 19

Distinctions between Preeclampsia and Eclampsia

1. What defines Preeclampsia?
2. Severe Preeclampsia?
3. Eclampsia?
4. HELLP Syndrome
5. Other complciations (3)

Answer 19

1. HTN, edema, proteinuria
2. preeclampsia + headache and vision changes
3. Preeclampsia + convulsions
4. severe preeclampsia + hemolysis, elevated liver enzynes, low platelets
5. hypercoaguability, acute renal failure, pulmonary edema

Question 20

Management of Preeclampsia- Eclampsia

1. If baby is at term
2. If baby is preterm
3. Long term consequences

Answer 20

1. deliver
2. mild- expectant management; severe- delivery regardless of fetal age
3. none for mother;
   20% of children develop HTN and microalbuminemia w/in 7 years;
   2x increased heart and brain vascular disease

Question 21

Placental Infections: Ascending

1. How common
2. How does it get there?
3. What causes it?
4. Result

Answer 21

1. more common
2. through birth canal
3. usually bacterial,
4. premature rupture of membranes, pre-term delivery

Question 22

Placental Infections: Hematogenous

1. How common
2. How does it get there?
3. What causes it?
4. What does it result in?

Answer 22

1. less common than ascending
2. hematogenous, blood spread
3. TORCH infections
4. neonate fever, encephalitis, chorioretinitis, hepatosplenomegaly, penumonitis, myocarditis, hemolytic anemia, and vesicular or hemorrhage skin lesions

Question 23

What are the TORCH infections?

Answer 23

Toxoplasma gondii
Others- (parvovirus B19, Syphilis, TB, listeria)
Rubella
CMV
HSV

Question 24

Gestastional Trophoblastic Disease

1. What is it?
2. Types (4)

Answer 24

1. tumors, proliferation of placental tissue (villous or trophoblastic)
2. Hydatiform mole (complete and partial)
   Invasive mole
   Choriocarcinoma
   Placental-site trophoblastic tumor (very rare)

Question 25

Hydatiform Moles 1. What are they? 2. How common? 3. Who is evaulated? 4. Why are they evaluated?

Answer 25

1. cystic swelling of chorionic villi with trophoblastic proliferation 2. infrequent in US, more common in China or Japan 3. most women who rpesent with miscarriage undergo D&C based on Uterus Size (US)/hCG findings 4. benign, but want to know and distinguish them with regard to increased risk of invasive mole or choriocarcinoma

Question 26

Complete Mole 1. What happens? 2. What happens to villi? 3. What can it make? 4. what happens to the embryo? 5. risk of what?

Answer 26

1. 2/3 sperm fertilize an empty ovum 2. most villi are enlarged & edematous; diffuse trophoblastic hyperplasia 3. androgens 4. dies very early, fetal parts rarely seen 5. 2.5% risk of choriocarcinoma

Question 27

Complete Mole 1. Gross look 2. Close-up Gross look 3. Microscopic

Answer 27

1. entire placenta, all villi edematous, delicate friable mass of thin-walled, translucent, cystic, grape like structures 2. villi look like balloons 3. Swollen villi with almost no fetal blood vessels; diffuse cytotrophoblast and syncytial trophoblastic proliferation; marked atypica at implantation

Question 28

Complete Mole 1. Clinical Course 2. Diagnostic Test 3. What is increased? 4. How is it removed? 5. What can develop?

Answer 28

1. abnormal uterine bleeding, passage of fluid and tissue 2. ultrasound (snow storm- larger than expected uterus) 3. serum hCG 4. curretage,serum hCG levels are followed 5. invasive moles (10%), choriocarcinoma (2.5%)

Question 29

Partial Mole 1. What happens? 2. What happens to villi? 3. Genomes 4. Is the fetus present? 5. What is risk for choriocarcinoma?

Answer 29

1. 2/3 sperm fertilize a normal ovum; 2. edematous 3. Triploid (69, XXY or 69,XXX) or tetraploid (92, XXXY) 4. fetus mostly present, although abnormal 5. NOT increased risk

Question 30

Partial Mole 1. Gross look 2. Microscopic look

Answer 30

1. some villous swelling, lots of solid parts | 2. swollen villus, trophoblast proliferation

Question 31

Invasive Mole 1. define 2. what can it do to distant sites? 3. Presentation 4. Risk of what? 5. Treatment

Answer 31

1. mole that penetrates uterine wall, hydropic chorionic villi invade myometrium 2. may embolize, does not disseminate 3. vaginal bleeding, persistantly elevated hCG 4. uterine rupture 5. chemotherapy

Question 32

Gestational Choriocarcinoma 1. Malignant or Benign? 2. course 3. What cells 4. How common? 5. What lesions/situations contribute to it?

Answer 32

1. Malignant; 2. rapidly invasive, widely metastatic; rapidly growing, 3. neoplasm of trophoblast derived cells 4. uncommon 5. 50% from complete moles 25% previous abortion 22% normal pregnancy (intraplacental choriocarcinoma) Ectopic pregnancy

Question 33

Choriocarcinoma 1. Gross look 2. Histo look 3. Presentation 4. When does it present? 5. How advanced is it at the time of presentation?

Answer 33

1. necrotic, hemorrhagic, rapidly growing 2. proliferation of neoplastic cystotrophoblasts and syncytiotrophoblasts (NO chorionic villi) 3. vaginal blood, brown fluid spotting 4. during pregnancy, after miscarriage, after curretage, can occur months after 5. usually already metastasized

Question 34

Choriocarcinoma 1. What is elevated? When is it not? 2. Treatment

Answer 34

1. hCG; unless necrotic | 2. surgery, chemo (extremely effective); paternal antigens evoke immune response in mothers

Question 35

Difference between ovarian and gestational choriocarcinoma 1. ovarian is result of... 2. response to chemo 3. what choriocarcinoma is rare?

Answer 35

1. extra-embryonic differentiation of malignant germ cells 2. ovarian- poorly responsive to chemo, poor prognosis 3. testis