Data were collected on nuchal translucency, chorionicity, pregnancy associated plasma protein-A (PAPP-A), and free ß human chorionic gonadotrophin (free ß-hCG) from 61 twin pregnancies with Down syndrome and 7302 unaffected twin pregnancies.
The overall prevalence of atypical chromosome abnormalities in the entire CFTS cohort was 0.10% and was highest in those with CFTS T21 risk > 1 in 10 (4.6%), or serum analyte levels < 0.2 multiples of the median (MoM) (6.9% for pregnancy-associated plasma protein-A (PAPP-A) and 5.2% for beta-human chorionic gonadotropin (β-hCG)).
Levels of pregnancy-associated plasma protein A (PAPP-A), soluble endoglin, pregnancy protein 13, and adiponectin (Adipo) were measured on residual sera used in first-trimester screening for Down syndrome.
Because maternal serum markers (pregnancy-associated plasma protein A, human chorionic gonadotropin free β subunit, and alpha-fetoprotein) used for Down syndrome (DS) screening have been described as predictors of obstetrical complications and because assisted reproductive technology (ART) pregnancies are known to be at increased risk for obstetrical complications, it is unclear whether or not correction factors should be applied to the calculated risk of DS.
The first trimester combined screening, which analyzes fetal nuchal translucency and levels of free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein A (PAPP-A) in maternal serum, is routinely used to detect abnormal pregnancies associated with Down syndrome and other trisomy aneuploidies.
A retrospective analysis was carried out on the free beta human chorionic gonadotrophin (beta-hCG) and pregnancy associated plasma protein-A (PAPP-A) levels and nuchal translucency thickness in 49 653 women with a normal singleton fetus who had first trimester combined screening for Down Syndrome in three centres.
To investigate the maternal serum concentration of human placental growth hormone (hPGH) in trisomy 21 and trisomy 18 pregnancies at 11 to 13 weeks of gestation and to examine the possible association between fetal nuchal translucency (NT) thickness and maternal serum free beta-human chorionic gonadotrophin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A).
In a screening policy based on maternal age, fetal NT, FHR, serum free beta-hCG and PAPP-A, for a fixed false positive rate of 3% the standardized detection rates were 91% for trisomy 21 and 100% for trisomy 18, trisomy 13 and Turner syndrome.
After detection of a significantly diminished maternal serum pregnancy-associated plasma protein A and correspondingly high DS risk, the pregnant woman underwent amniocentesis for fetal chromosomal analysis.
First trimester Down's syndrome screening marker values and cigarette smoking: new data and a meta-analysis on free beta human chorionic gonadotophin, pregnancy-associated plasma protein-A and nuchal translucency.
Maternal serum PAPP-A below the 5th centile was associated with Down syndrome (OR 8.43), spontaneous loss before 24 weeks (OR 5.04) and later than 24 weeks (OR 4.50), preterm delivery before 32 weeks (OR 3.11) and before 37 weeks (OR 2.24).
NT was measured according to the criteria set by The Fetal Medicine Foundation (FMF), maternal serum free beta-hCG and PAPP-A levels were measured, and the risk of trisomy 21 was calculated using The FMF's algorithm.
We examined 54,722 singleton pregnancies with no chromosomal abnormality and with complete outcome data that had undergone screening for trisomy 21 by a combination of fetal nuchal translucency (NT) thickness, maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11 + 0 and 13 + 6 weeks' gestation.
Maternal serum free beta-human chorionic gonadotropin (beta-hCG) and pregnancy-associated plasma protein-A (PAPP-A) have been used effectively in the screening of Down syndrome in the first trimester.
To assess whether there is a need to correct first-trimester biochemical markers (free beta-hCG and pregnancy-associated plasma protein-A (PAPP-A)) or first-trimester fetal nuchal translucency thickness (NT) in different ethnic groups, when screening for Downs syndrome at 11-14 weeks of gestation.
A first-trimester integrated screening approach, which incorporates nuchal translucency, nasal bone, crown-rump length, pregnancy-associated plasma protein-A, and free beta-human chorionic gonadotropin, has the potential to maximize detection rates of Down syndrome and trisomy 18 and minimizes the screen-positive rate.
The efficiency of six maternal serum markers for Down's syndrome (DS), alpha fetoprotein (AFP), human chorionic gonadotropin (hCG), free beta-hCG, pregnancy-associated plasma protein-A (PAPP-A), the proform of eosinophil major basic protein (ProMBP), pregnancy-specific-beta-1-glycoprotein (SP(1)), and combinations thereof, was examined.
Fetal trisomies 21, 18, and 13 are associated with a reduction in second-trimester maternal PAPP-A levels; trisomies 18 and 13 are not associated with increased inhibin A levels, unlike trisomy 21.
Since we were in the phase of collecting data for the Finnish medians for PAPP-A and beta-hCG, the women were not given the estimates of risk for trisomy 21.
Studies of first-trimester serum screening with measurements of pregnancy-associated plasma protein A and free beta-human chorionic gonadotropin serum concentrations have been much more consistent, with Down syndrome detection rates of 55% to 63% at a 5% false-positive rate.
Early pregnancy screening with the combined measurement of maternal serum PAPP-A and free beta-hCG and fetal nuchal translucency could achieve a high Down syndrome detection rate.
Patients were evaluated for risk of Down's syndrome and trisomy 18 based on biochemistry (free beta-human chorionic gonadotropin and pregnancy-associated plasma protein A), nuchal translucency and the combination of both.
There was however a significant association between placental protein and maternal serum PAPP-A concentrations in the normal and trisomy 21 pregnancies but not in those affected by trisomy 18.