Pregnancy-associated plasma protein-A (PAPP-A) is a protein found in the maternal circulation and is produced by the placenta. The PAPP-A gene has been assigned to human chromosome 9q33.1 and contains 22 exons 5. PAPP-A values tend to rise exponentially during pregnancy and the reference range depends on the stage of gestation. The common practice is to use the unit multiple of median (MoM) as a gestational age-dependent expression of PAPP-A concentration.
Low maternal serum PAPP-A levels in the first trimester have been associated with a wide range of fetal pathology and pregnancy-related complications 1-4:
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- 5. Shiefa S, Amargandhi M, Bhupendra J et-al. First Trimester Maternal Serum Screening Using Biochemical Markers PAPP-A and Free β-hCG for Down Syndrome, Patau Syndrome and Edward Syndrome. Indian J Clin Biochem. 2013;28 (1): 3-12. doi:10.1007/s12291-012-0269-9 - Free text at pubmed - Pubmed citation
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