SFP: placenta and pregnancy

Question 1

What is spontaneous abortion?

Answer 1

Pregnancy loss before 20 weeks gestation.

Question 2

What is threatened spontaneous abortion?

Answer 2

Uterine bleeding without cervical dilation.

Question 3

What is inevitable spontaneous abortion?

Answer 3

Uterine bleeding with dilation or effacement.

Question 4

What typically causes spontaneous abortion?

Answer 4

Fetal issues, like karyotype, chromosomal abnormalities, and fetal structure.

Question 5

What is ectopic pregnancy?

Answer 5

Implantation outside of the uterus; usually in the fallopian tube.

Question 6

What are risks for ectopic pregnancy?

Answer 6

Scarring (PID, tubal surgery, etc).

Question 7

What happens if an ectopic pregnancy ruptures?

Answer 7

It is a medical emergency; the patient can experience hemorrhagic shock due to bleeding in the peritoneum.

Question 8

What is placenta previa?

Answer 8

The placenta is located over the internal cervical os.

Question 9

Who is placenta previa more common in?

Answer 9

Older women.

Question 10

What is placenta previa associated with?

Answer 10

Multiparity, previous C-section, male infants.

Question 11

What is vasa previa?

Answer 11

Fetal vessels located over the cervical os.

Question 12

What is velamentous cord insertion?

Answer 12

Umbilical cord inserts into extra villous membranes surrounding the placental disc instead of the center of the placental disc. This puts the cord over the os and creates the potential for rupture and bleeding during delivery.

Question 13

What is a bilobed placental disc?

Answer 13

Two placental discs connected by chorionic vessels not connected by the umbilical cord; poses a risk for vessel rupture.

Question 14

What is true of a vaginal exam in previa?

Answer 14

It is contraindicated!!

Question 15

What is placenta accreta spectrum?

Answer 15

Placenta implants past the decidua and into the myometrium; this will cause the placenta to be abnormally adherent and not deliver properly after the fetus.

Question 16

What is a huge cause of post-partum bleeding?

Answer 16

Placenta accreta.

Question 17

How can we diagnose placenta accreta before delivery?

Answer 17

Ultrasound or MRI.

Question 18

What are the routes of placental infection?

Answer 18

1. Ascending from vagina 2. Trans-placental TORCH infections.

Question 19

Describe maternal inflammatory response to placental infection.

Answer 19

RBCs and neutrophils travel toward the surface to fight infection. There will also be bacterial colonies on the surface and potentially loss of cuboidal epithelium.

Question 20

Describe fetal inflammatory response to placental infection.

Answer 20

Neutrophils marginate from umbilical vessels toward the amnion to fight the infection; may see necrosis around the vessel.

Question 21

What are complications of chronic or severe placental infection?

Answer 21

Prematurity, congenital pneumonia and sepsis, neuro-disability, fetal death.

Question 22

What are TORCH infections?

Answer 22

Those that cross the placenta; toxo, syphilis, CMV, parvo, HSV.

Question 23

What causes chronic placental infections?

Answer 23

Active infection or reactivation of latent infection.

Question 24

Describe congenital CMV.

Answer 24

Most common congenital infection; may cause hearing loss, seizures, petechial rash (blueberry muffin rash).

Question 25

How do we do prenatal screening for congenital CMV?

Answer 25

We don’t…not much we can do.

Question 26

What is chronic villitis of unknown etiology?

Answer 26

A sort of transplant rejection of parental and fetal antigens in the placenta that causes inflammatory lesions.

Question 27

What is seen on histology in chronic villitis of unknown etiology?

Answer 27

Inflammatory cells (lymphocytes) destroying chorionic villi.

Question 28

What are outcomes of chronic villitis of unknown etiology?

Answer 28

Fetal growth restriction, fetal demise.

Question 29

Describe fetal vascular malperfusion.

Answer 29

Obstruction of fetal flow to chorionic villi, usually due to umbilical abnormality that impacts flow but also anything that can cause thrombus.

Question 30

Describe maternal vascular malperfusion.

Answer 30

Obstruction of maternal flow to intervillous spaces, often a cause of preeclampsia.

Question 31

What does the placenta look like in MVM?

Answer 31

Hypoplastic placenta that is small compared to the fetus.

Question 32

What is decidual arteriopathy?

Answer 32

Pathology of decidual arteries seen in MVM; there will be foamy macrophages and necrosis.

Question 33

What is accelerated villous maturation?

Answer 33

More mature placenta, likely a compensatory mechanism from hypoxia that attempts to have more mature villi to get more nutrient exchange/blood.

Question 34

What is villous infarction?

Answer 34

Seen if there is a complete block of flow from decidual arteries.

Question 35

What is the clinical triad of preeclampsia?

Answer 35

HTN, proteinuria, edema.

Question 36

What is preeclampsia thought to be caused by?

Answer 36

Abnormal placental remodeling of spiral arteries.

Question 37

What is eclampsia?

Answer 37

Addition of maternal seizures.

Question 38

What is HELLP syndrome?

Answer 38

Variant of preeclampsia with Hemolysis, elevated LFTs, low platelets.

Question 39

How do we treat preeclampsia?

Answer 39

Delivery of the placenta.

Question 40

What is placental abruption?

Answer 40

Premature separation of the placenta from the uterine wall.

Question 41

What is a concealed hemorrhage in placental abruption?

Answer 41

Confined to the uterine cavity.

Question 42

What is a revealed hemorrhage in placental abruption?

Answer 42

Blood dissects to the cervix.

Question 43

What are monozygous twins?

Answer 43

One egg fertilized with one sperm.

Question 44

What are placental types possible in twins?

Answer 44

1. Monochorionic/monoamniotic: one shared placenta, no dividing membrane 2. Monochorionic diamniotic: one shared placenta, presence of dividing membrane 3. Dichorionic diamniotic: separate placentas and dividing membrane.

Question 45

Dizygous twins have what placenta type?

Answer 45

Dichorionic diamniotic.

Question 46

What is twin-twin transfusion syndrome?

Answer 46

Vascular anastomoses between twins that cause shunting of blood to one twin; one will be hydropic and red, and the other will be small and pale. May result in death of one or more fetuses.

Question 47

What is gestational trophoblastic disease?

Answer 47

Tumors and tumor-like conditions characterized by proliferation of placental tissue.

Question 48

What is a complete hydatiform mole?

Answer 48

Trophoblastic tissue without fetal tissue; causes risk for choriocarcinoma.

Question 49

Describe the appearance of complete moles.

Answer 49

Hydropic, swollen chorionic villi and extensive trophoblast proliferation that causes lots of bHCG production. ALL villi are hydropic.

Question 50

What is a partial hydatiform mole?

Answer 50

Trophoblastic tissue with fetal tissue; usually from extra paternal chromosome set.

Question 51

What is choriocarcinoma?

Answer 51

Malignant tumor of cyto and syncytiotrophoblast associated with previous pregnancy. May follow a complete mole, miscarriage, and normal pregnancy.

Question 52

What is true of blood supply of choriocarcinoma?

Answer 52

They invade blood vessels and spread hematogenous. They have no inherent supply so are often necrotic.