SP1 in pregnancies with Down syndrome in the first trimester of pregnancy. International Prenatal Screening Research Group.
We conducted a study to determine the value of serum pregnancy-specific beta-1-glycoprotein (Schwangerschafts protein 1, SP1) as an antenatal screening test for Down syndrome in the first trimester. Serum samples collected from women at 8 to 14 weeks of pregnancy, immediately prior to having a chorionic villus sampling procedure on account of advanced maternal age, were retrieved from 96 women with Down syndrome pregnancies (cases) and from 480 women with unaffected pregnancies (controls). Cases and controls were ascertained at 21 obstetric centres in nine countries. Each case was matched with five controls for maternal age (same five-year age groups), duration of storage of the serum sample (same calendar year) and gestational age (usually the same week of pregnancy). The levels of SP1 were lower in pregnancies associated with Down syndrome: the median level was 0.86 multiples of the median level in the controls (95 per cent confidence interval 0.76 to 0.97). This difference, though statistically significant, was not large enough for SP1 to be a useful marker in screening, at least from 10 weeks onwards where most of our data lie.
Department of Environmental and Preventive Medicine, Wolfson Institute of Preventive Medicine, St Bartholomew's and the Royal London School of Medicine and Dentistry, Charterhouse Square, UK. n.j.wald@mds.qmw.ac.uk
N J
NJ
Wald
H C
HC
Watt
B
B
Norgaard-Pedersen
M
M
Christiansen
D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000097:blood*; D011268:Pregnancy-Specific beta 1-Glycoproteins / Q000032:analysis*; D011296:Prenatal Diagnosis / Q000379:methods*; D012044:Regression Analysis
D015415:Biomarkers; D011268:Pregnancy-Specific beta 1-Glycoproteins