PAPP-A
Pronunciation: pap-AY
Also written as: PAPP-A — Pregnancy-Associated Plasma Protein A
Pregnancy-associated plasma protein A, a biomarker measured in first-trimester screening for chromosomal abnormalities.
Full Definition
Pregnancy-associated plasma protein A (PAPP-A) is a glycoprotein produced by the placenta and measured as part of first-trimester combined screening for Down syndrome and other chromosomal abnormalities. Low levels of PAPP-A are associated with increased risk of trisomy 21, trisomy 18, and intrauterine growth restriction. The protein is measured between 9-14 weeks of gestation alongside free beta-hCG and nuchal translucency measurement. PAPP-A levels are expressed as multiples of the median (MoM) and incorporated into risk calculation algorithms. Very low PAPP-A levels may also indicate increased risk of pregnancy complications including preeclampsia and stillbirth.
Usage
Usage note: Always hyphenated and capitalized when abbreviated.
In Context
- "First-trimester screening showed PAPP-A levels at 0.3 MoM, indicating increased risk." — Laboratory report
- "The low PAPP-A result prompted discussion of invasive diagnostic testing options." — Clinical consultation