Correlations between maternal hepatitis B virus carrier status and Down's syndrome prenatal screening indicators and their effects on the screening results.

The aim of this study was to determine the correlation between maternal hepatitis B virus (HBV) carrier status and pregnancy-associated serum screening indicators, as well as their implications on the prenatal screening results of Down's syndrome (DS). This retrospective cohort study included two groups, namely the healthy gravidas group ( n  = 19804) and the maternal HBV carrier group ( n  = 792). Serum pregnancy-associated plasma protein A (PAPP-A), alpha-fetoprotein (AFP), and free beta subunit of human chorionic gonadotropin (free β-hCG) levels, as well as the foetal nuchal translucency (NT) thickness, were measured. Multivariatebinary logistic regression analysis was used to evaluate the association between the HBV carrier status and prenatal screening biomarkers. The PAPP-A multiple of the medium (MoM) and free β-hCG MoM in the first trimester were significantly higher in the HBV carrier group than in the control group (both P  < .05). Multivariate binary logistic regression analysis showed that HBV carrier status was identified as a risk factor for PAPP-A and the intrahepatic cholestasis of pregnancy (ICP), with adjusted odds ratios (aOR) of 1.363 (1.216-1.527) and 3.255 (2.356-4.499), respectively. Pregnant women with HBV carrier status had higher influence on serum PAPP-A level and ICP, and the risk calculation algorithm for DS in HBV carriers should be corrected in the first trimester of pregnancy. IMPACT STATEMENT What is already known on this subject? The maternal serum levels of pregnancy-associated plasma protein A (PAPP-A), alpha-fetoprotein (AFP), and free beta subunit of human chorionic gonadotropin (free β-hCG), as well as the foetal nuchal translucency (NT) thickness, have been collectively used in the prenatal screening of Down's syndrome (DS), Edward's syndrome (ES), and open neural tube defects (ONTD). However, many factors, including the maternal age; maternal weight; gestational age; race; history of smoking and so on can affect those serum biomarker levels. Our aim is to know whether there is a difference for HBV status to pregnancy-associated serum screening indicators hoes. What the results of this study add? The PAPP-A multiple of the medium (MoM) and free β-hCG MoM in the first trimester were significantly higher in the HBV carrier group than in the control group (both p < .05). Multivariate binary logistic regression analysis showed that the PAPP-A and intrahepatic cholestasis of pregnancy (ICP) were risk factors for HBV carriers, with aORs of 1.363 (1.216-1.527) and 3.255 (2.356-4.499), respectively. What the implications are of these findings for clinical practice and/or further research? The PAPP-A MoM in maternal HBV carriers was significantly higher than that in healthy gravidas, and the risk calculation algorithm for DS in maternal HBV carriers should be corrected in the first trimester of pregnancy.