CaseFiles_2 Flashcards
(48 cards)
The most common causes of abnormal serum triple test screening are
wrong dates and multiple gestations (assess via obstetric ultrasound)
What is the uterine height when it is the appropriate time for serum testing for Down’s, trisomy 18, and neural tube defects? What are the chemicals that are analyzed?
16-20 weeks (15-21). 16 weeks: fundus midway between symphysis pubis and the umbilicus. At 20 weeks: fundal height at umbilicus.
AFP, hCG, and unconjugated estriol (“triple screen”)
What is alpha-fetoprotein?
A glycoprotein made by the yolk sac and later by fetal liver/GI tract, analogous to albumin
What is first trimester screening?
performed between 10 and 13 weeks. PAPP-A, B-hCG and nuchal translucency for risk of Down or trisomy 18
AFP levels greater than ______ multiples of the median (MOM) are suspicious for neural tube defects. What are other causes of this level?
2-2.5
Can also be caused by multiple gestations, underestimation of gestational age, abdominal wall defects, oligohydramnios, and fetal skin defects.
Down syndrome is associated with (high/low) AFP. What are other causes of a similar AFP level?
LOW AFP. Also caused by molar pregnancy, fetal death, increased maternal weight, overestimation of gestational age.
What are the results of the triple test in Down syndrome?
1) AFP: low
2) hCG: high
3) unconjugated estriol: low
* *note, sometimes they add inhibin A: high
What are the results of the triple test in Edwards Syndrome?
1) AFP: low
2) hCG: low
3) unconjugated estriol: low
What are the results of the first trimester screening for the trisomies?
Trisomy 21: PAPP-A low, BhCG high, nuchal transulency low (thick!!!)
Trisomy 13 and 18: PAPP-A low, BhCGlow (nuchal transulency thick?)
What are findings on ultrasound suspicious for Down syndrome?
1) thickend nuchal fold
2) shortened femur length
3) echogenic bowel
What are the teratogenic effects of ACE-I?
skull anomalies, limb defects, miscarriage, renal failure in neonate, renal tubule dysgenesis, oligohydramnios
When does organogenesis occur in gestation?
Days 15-60
A double-bubble sign indicates ____________, related to what genetic abnormality?
duodenal atresia, associated with Down Syndrome
Pregnancies with elevated msAFP, which after evaluation are still unexplained, are at increased risk for:
stillbirth, growth restriction, preeclampsia, and placental abruption
Teratogenic exposure prior to ___ weeks gestation leads to an “all or nothing” effect.
2
What is velamentous cord insertion?
umbilical vessels separate before reaching the placenta, protected only by a thin fold of amnion, instead of by the cord or the placenta itself
The incidence of vasa previa (umbilical vessels not protected by cord or membranes crossing the internal cervical os in front of the fetal presenting part) is (increased/decreased) in IVF?
Increased
Complications associated with twin gestation (x5):
1) preterm delivery
2) congenital malformations (esp in monozygotic)
3) preeclampsia
4) postpartum hemorrhage
5) twin-twin transfusion syndrome
6) gestational diabetes
7) DVTs
How is the use of OCPs related to twinning?
Since OCPs slow tubal motility (though to lead to monozygotic twinning), you should know if a mother used OCPs within 3 months of becoming pregnant
Monozygotic twins are associated with a (higher/lower) incidence of discordant growth and malformations.
(Mono/di)chorionic twins are associated with a higher rate of spontaneous abortion.
Monozygotic = higher risk of malformations Monochorionic = higher rate of spontaneous abortion
How dos timing of division affect the chorionicity/amnionicity of monozygotic twins?
If timing of division is within:
1) 72 hours: dichorionic/diamniotic
2) Day 4-8: monochorionic/diamniotic
3) Day 8-12: monochorionic/monoamniotic
4) After day 12: conjoined
The rate of dizygotic twinning (increases/decreases) with age and peaks at ___ years.
increases; 37 years
What is the chorionicity/amnionicity of all dizygotic twins?
All dizygotic twins are dichorionic and diamniotic
Why is there greater physiologic anemia in a twin pregnancy?
Blood volume and stroke volume are increased more than singleton pregnancy, but the red cell mass increases proportionately less
