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Updated: Sep 25, 2026

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Published on: September 5, 2011
Early vaginal bleeding and first-trimester markers for Down syndrome
Pierangela De Biasio1, Silvana Canini, Angela Crovo
1UO di Ostetricia e Ginecologia, Istituto "G Gaslini", Università di Genova, Italy. bnhdeb@libero.it
Objectives:
To assess the effect of early vaginal bleeding on first-trimester markers for Down syndrome.
Methods:
A retrospective study was conducted on 2330 normal singleton fetuses who underwent first-trimester combined screening for Down syndrome based on ultrasound and maternal serum markers. Fetal nuchal translucency (NT), maternal serum pregnancy-associated plasma protein A (PAPP-A), free beta-hCG and the false-positive rate of the test were compared between pregnancies with (n = 253) and without (n = 2077) a history of early vaginal bleeding.
Results:
The mean +/- SD log(10) MoM for NT, PAPP-A and free beta-hCG was -0.024 +/- 0.101, 0.007 +/- 0.244, 0.047 +/- 0.273 and -0.011 +/- 0.108, -0.006 +/- 0.223, 0.008 +/- 0.264 in pregnancies with and without a history of early vaginal bleeding, with a p value of 0.07, 0.40 and 0.03 respectively. The false-positive rate was 2.4% and 3.6% (p = 0.33).
Conclusions:
An earlier episode of vaginal bleeding is associated with an increase in maternal serum free beta-hCG levels at first-trimester combined screening for Down syndrome. However, this phenomenon is unlikely to significantly affect the false-positive rate of the test.
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