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.
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.
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).
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.
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.
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.
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.