Genetic Abnormalities – Biology Test 12
The key terms of Biology Test include, Genetic Abnormalities.
Second-trimester amniocentesis for fetal genetic abnormalities is best performed between ———- and ———– weeks because the amniotic fluid is of adequate volume and contains many viable fetal cells.
15, 20
Positive
Late decelerations follow 50% or more of contractions, even if fewer than three contractions occur in 10 minutes.
Non-reassuring CST
NST, fetal breathing movements, gross fetal movements, fetal tone, amniotic fluid volume
BPP components
Blood test that ascertains info about likelihood of fetal birth defects. Includes AFP, hCG, Estriol, Inhibin-A
THOUGH IT DOES NOT ACTUALLY DIAGNOSE DEFECT
Quad marker screening
Pregnancies complicated by hypertension or fetal growth restriction caused by placental insufficiency can be assessed using
Doppler ultrasound
Also called Cordocentesis, involves the aspiration of fetal blood from the umbilical cord near the placenta for prenatal diagnosis or therapy
PUBS is infrequently needed to determine the Karyotype (chromosome evaluation)
Purcutaneous Umbilical Blood Sampling (PUBS)
Amniocentensis can be performed during the third trimester to evaluate ——– ——— ——— or Rh incompatibility problems.
Fetal lung maturity
Safe, noninvasive, painless; transducer moved over abdomen; useful after first trimester when gravid uterus is larger; requires full bladder
External abdominal ultrasound
Most common method of fetal blood sampling/transfusion
Blood is aspirated through the umbilical vein, fine gauge fetoscope is guided via amniocentesis technique
Precutaneous umbilical blood sampling
The most common cause of ——————– AFP is failure of the embryonic neural tube or anterior body wall to close properly.
Second-trimester amniocentesis for fetal genetic abnormalities is best performed between ———- and ———– weeks because the amniotic fluid is of adequate volume and contains many viable fetal cells.
15, 20
Positive
Late decelerations follow 50% or more of contractions, even if fewer than three contractions occur in 10 minutes.
Non-reassuring CST
NST, fetal breathing movements, gross fetal movements, fetal tone, amniotic fluid volume
BPP components
Blood test that ascertains info about likelihood of fetal birth defects. Includes AFP, hCG, Estriol, Inhibin-A
DOES NOT ACTUALLY DIAGNOSE DEFECT
Quad marker screening
Pregnancies complicated by hypertension or fetal growth restriction caused by placental insufficiency can be assessed using
Doppler ultrasound