Gestational and Placental Disorders Flashcards
What is the function of the placenta?
Establish effective communication between mother and developing fetus while maintaining immune and genetic integrity of both individuals.
Amnion
Inner layer of the amniotic cavity
Chorion
Outer layer of the amniotic cavity
Decidua
The endometrium of pregnancy and where the chorion attaches
Chorionic Villi
They sprout from the chorion to provide a large contact area between fetal and maternal circulations
Do the maternal and fetal blood mix?
Under normal circumstances maternal and fetal blood do not “mix”.
What is the main cause of spontaneous abortions?
Chromosomal abnormalities
Ectopic Pregnancy
Implantation of embryo occurs outside of the uterus
What kind of chorion implies identical twins?
Monochorionic
Placenta Previa
Attachment of placenta to lower uterine segment or cervix that causes 3rd trimester bleeding as the cervix dilates.
Placenta Accreta
Partial or complete absence of decidua with adherence of placental villous tissue directly to myometrium which causes postpartum bleeding.
What are some predisposing factors for placenta accreta?
– Placenta previa
– Hx previous cesarean section
Abruptio Placentae
Premature separation of placenta prior to delivery leading to the formation of retroplacental blood clot - can compromise the blood supply to the fetus
What process fails in preeclampsia-eclampsia?
Cytotrophoblasts outside invade the vasculature
in the media and allow them to remodel and be more
accommodating which fails in preeclampsia-eclampsia.
What are some risks for preeclampsia-eclampsia?
- HTN
- DM
- Obesity
- Very young or very old
What are the features of preeclampsia?
- HTN
- Edema
- Proteinuria
Severe Preeclampsia
Preeclampsia with headaches and vision changes
Eclampsia
Preeclampsia with convulsions
HELLP Syndrome
Severe preeclampsia with hemolysis, elevated liver
enzymes and low platelets.
What must be done for treatment of preeclampsia-eclampsia?
If the disease is severe, delivery must be done regardless of fetal age
What are drugs used to treat maternal HTN?
- Labetalol
- Methyldopa
- Hydralazine
What is the most common pathway for placental infection?
Ascending infection. Hematogenous spread is much more uncommon.
What will be seen histologically with Acute Chorioamnionitis?
PMN infiltrates. Green color on gross specimen.
What are the TORCH infections?
- Toxoplasma gondii
- O –Others Parvovirus B 19, Syphillis, TB, listeria
- Rubella
- CMV
- HSV and HIV
Features of these illnesses in the neonate include: fever, encephalitis, chorioretinitis, hepatosplenomegaly, pneumonitis, myocarditis, hemolytic anemia and vesicular or hemorrhagic skin lesions.
TORCH Infections
Cystic swelling of chorionic villi with trophoblastic proliferation.
Hydatiform Moles
What is a lab characteristic of hydatiform moles?
Elevated hCG
Complete Mole
- Most villi are enlarged
- Made from 2 sperms fertilizing empty ovum OR one sperm that has DNA copied to diploidy
- Embryo dies early -> rarely see fetal parts
Partial Mole
- Only some villi are edematous
- Made from one egg and 2 or more sperm (minimum triploidy)
Is there an increased risk of choriocarcinoma with partial mole?
No
Invasive Mole
• Mole that penetrates uterine wall
• Hydropic chorionic villi invade myometrium
– May embolize to distant sites
Gestational Choriocarcinoma
Malignant, invasive and widely metastatic and is a neoplasm of trophoblast derived cells
- Proliferationof neoplastic cystotrophoblasts and syncytiotrophoblasts
- NO chorionic villi
- Presents as vaginal blood, brown fluid spotting
Gestational Choriocarcinoma
How effective is chemotherapy in gestational choriocarcinoma?
VERY effective
