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
