Maternal serum CA 19-9 and CA 15-3 levels in pregnancies affected by trisomy 21

ABSTRACT Objectives To investigate the levels of tumour markers CA 19–9 and CA 15–3 in the first trimester maternal serum of euploid control and trisomy 21 pregnancies. Methods Maternal serum marker levels of 69 trisomy 21 and 388 euploid controls were quantified by the Kryptor analyser, and levels were compared between the two groups after analysis for confounding factors. Monte Carlo simulation was carried out to determine the effect of adding potential markers to the combined test. Results Neither marker was affected by gestational age; however, CA 19–9 required correction for maternal weight. CA 19–9 was significantly increased in trisomy 21 pregnancies (0.98 MoM in euploid, 1.16 MoM in trisomy 21, p = 0.024). Levels of CA 15–3 were not found to differ significantly (1.03 MoM in euploid, 1.09 in trisomy 21, p = 0.130). Detection rates were unaffected by addition of CA 19–9 to the combined test. Conclusion Although a small significant increase in CA 19–9 levels was found in trisomy 21 group, it is unlikely to be of any use as part of a trisomy 21 screening tool. © 2012 John Wiley & Sons, Ltd.