Lec 11 High Risk OB Flashcards
What percentage of twins are identical vs fraternal?
1/3 identical
2/3 frateernal
What kind of twinning is inherited?
double ovum [fraternal] are inherited
single ovum [identical] are due to chance splitting of the ovum
What do the numbers in G2P1001 mean?
G = number of pregnancies P = number of deliveries; 4 digits = TPAL --> term pregnancies, preterm births, abortions/miscarriages, living children
How do you get monozygotic twins?
fertilization of single ovum by single sperm after which zygote divides
usually have 1 placenta with 1 chorion [monochorionic] and 2 amnions [diamnionic]
How do you get monozygotic dichorionic diamnionic twins?
split before day 3
What are risk factors for dizygotic twins?
- multiple ovulations
- increase incidence with increasing maternal age up to 40
- increased parity
How do you get monozygotic monochorionic diamnionic twins?
split days 3-8
How do you get monozygotic monochornionic monoamnionic twins?
days 8-13 split
How do you get conjoined twins?
split after day 13
What are the hazards of twin gestation?
- preterm delivery
- discordant fetal growth
- pregnancy induced hypertension
- anemia
- increased risks of preeclampsia
What are signs of preeclampsia?
- hypertension > 140/90 after 20 wks with previously normal BP
- proteinuria > 300 mg in 24 hr
- symptoms = headache, RUQ pain
What is HELLP syndrome?
preeclampsia PLUS:
- hemolysis
- elevated liver enzymes
- low platelets
What is eclampsia?
new onset grand mal seizures in a woman with preeclampsia
What are risk factors for preeclampsia?
- primagravid
- chronic htn
- diabetes
- chronic renal disease
- auoimmune disease
What causes preeclampsia?
abnromal placental spiral arteries –> causes matenal endothelial dysfunction, vasoconstriction, or hyperreflexia
What do you give to patient wtih preeclampsia to prevent seizures?
magnesium sulfate
What do you see on pathology with preeclampsia?
small placenta with multiple infarcts; placental trophoblast cells may not have adequately invaded maternal blood vasculature
What is a hydatidiform mole?
benign placental neoplasm with excess paternal chromosomes
What do you see in complete mole pregnancy?
all the placental chorionic villi are abnormal
no fetus
46 XX or 46 XY
What do you see in a partial mole pregnancy?
some villi are normal others are not
69 XXX, 69 XXY, or 69 XYY
