Purpose: To assess the mid-trimester triple test biomarkers among women diagnosed with vasa previa (VP).
Methods: The study included 43 singleton pregnancies diagnosed with vasa previa between the years 1988 and 2011. The mid-gestation screening test for Down syndrome was calculated from the combination of triple serum markers and maternal age, and expressed as a multiple of the gestation specific normal mean (MoM). Reference MoM values were calculated from the local population. The levels of mid-gestation maternal serum alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3) of patients with VP were compared with control reference group.
Results: The mean hCG and αFP levels of women diagnosed with VP was significantly higher compared to control reference group (1.42 versus 0.99 MoM; p < .002 and 1.24 versus1.01 MoM; p < .001, respectively). In contrast, there was no significant difference in uE3 levels between these two groups (0.99 versus 0.98 MoM; p = .71).
Conclusions: Our findings suggest that increased mid-gestation hCG and AFP were found among pregnancies complicated with VP. Clinicians should consider targeted scanning of pregnant women with risk factors for VP, including unexplained high maternal levels of hCG and αFP of the triple test, while conducting mid-gestation anomaly scan.
Keywords: AFP; hCG; mid-gestation triple test serum markers; prenatal; ultrasound; vasa previa.