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This screening test was the first noninvasive serum analyte-based screening test developed to identify pregnancies with an increased risk for a fetal open neural tube defect (NTD).
What is maternal serum alpha-fetoprotein (MSAFP) screening?
This is a screening technique that evaluates the fetus mainly for aneuploidies (and other features) by analyzing circulating placental cell-free DNA in the maternal blood via high-throughput DNA sequencing technologies.
What is cell-free DNA-based noninvasive prenatal screening (NIPS)?
This is an assessment done around week 8 - 12, which evaluates fetal viability, number, size, gestational age, nuchal translucency (NT), and major structural anomalies, if any.
What is the first trimester ultrasound/ultrasonography?
This diagnostic procedure is typically performed between 10 and 14 weeks of pregnancy
What is Chorionic Villus Sampling (CVS)?
Historically, this maternal factor was the most common reason for referral for invasive testing to check for trisomies
What is Advanced Maternal Age (AMA)?
This screening relies on measuring the levels of pregnancy-associated plasma protein A (PAPP-A) and the hormone human chorionic gonadotropin (hCG) in the maternal serum, and the results are combined with ultrasonographic measurements of the nuchal translucency (NT).
What is first trimester screening?
This is the detection rate (sensitivity) of cell-free DNA-based NIPS for Trisomy 21.
What is 99.7%?
This is a targeted ultrasound exam, which provides a more detailed examination of the fetal heart.
What is fetal echocardiography?
This is the approximate risk for inducing a miscarriage during a mid-trimester amniocentesis performed at 16 to 20 weeks
What is 1 in 909?
If a 30-year-old woman has previously had a child with down syndrome, her recurrence risk for any chromosomal abnormality in a future pregnancy is approximately this
What is 1 in 100 or 1%?
This group of tests measures the hormone human chorionic gonadotropin (hCG) levels in combination with maternal serum alpha-fetoprotein (MSAFP), unconjugated estriol (uE3), and inhibin A.
What is a quadruple screen?
These are the cells from which the placental cell-free DNA fragments (present in the maternal circulation during pregnancy) are derived from.
What are trophoblasts?
This is a term used to describe an anomaly that is not syndromic and could be found in a chromosomally normal fetus.
What is an isolated anomaly?
Unlike amniocentesis, CVS cannot be used to diagnose open neural tube defects (NTDs) because it cannot measure this specific analyte
What is amniotic fluid α-fetoprotein (AFAFP)?
This parental chromosomal rearrangement carries a 100% risk for Down syndrome in offspring
What is a 21q21q Robertsonian translocation?
Lowering the maternal serum alpha-fetoprotein (MSAFP) concentration cut-off value in the screening test improves sensitivity, but it does so by reducing this other test parameter, thus leading to more false-positive results.
What is specificity?
This is an approach used to screen for aneuploidies, where the total cell-free DNA is sequenced via next generation sequencing, and millions of DNA molecules are each mapped to their particular chromosome of origin, and then counted to determine if the number of sequences for that particular chromosome is abnormal or not.
What is the counting approach used in cell-free DNA screening for aneuploidies?
Please refer to "Jeopardy (Template 1) - Image 1" on the slides.
What is the double bubble sign in duodenal atresia?
Performing amniocentesis before 15 weeks is no longer recommended because it increases the risk of fluid leakage, miscarriage, and this orthopedic deformity
What is talipes equinovarus (clubfoot)?
This specific ultrasound measurement, when found to be increased, is associated with a greater risk for aneuploidy
What is Nuchal Translucency (NT)?
In the first trimester screening, an increased probability of these chromosomal conditions is suggested by an increase in nuchal translucency (NT), a decrease in pregnancy-associated plasma protein A (PAPP-A) levels, and a decrease in free beta human chorionic gonadotropin (βhCG) hormone levels compared to the average values.
What is Trisomy 13 and 18?
In NIPS, as this parameter decreases, the Positive Predictive Value (PPV) decreases, whereas the Negative Predictive Value (NPV) increases.
What is prevalence of a condition in regards to the accuracy of NIPS?
Please refer to "Jeopardy (Template 1) - Image 2" on the slides.
What is cystic hygroma?
A patient’s CVS results at 11 weeks show a chromosomal mosaicism. To determine if this abnormality is truly present in the fetus or if it is Confined Placental Mosaicism (CPM), what is the next diagnostic step and why?
What is a follow-up amniocentesis to establish the fetal karyotype?
This term refers to a fetus that has failed to achieve its genetic growth potential, often due to intrinsic genetic limitations
What is Fetal Growth Restriction (FGR)?