['Paraoxonase/arylesterase activities are closely implicated with liver function and antiatherogenetic process.', 'To evaluate whether maternal chronic hepatitis B virus, disease (HBV) affect serum neonatal paraoxonase/arylesterase activities.', '28 pregnant women with HBV and 28 healthy pregnant women (controls) in the delivery room and their newborns (cord blood) underwent laboratory examinations. Serological virus tests and liver function tests and paraoxonase (PON 1) activities were measured with the Siemens Advia 1650 Clinical Chemistry System, while total antioxidant capacity (TAC) levels and paraoxonase-arylesterase (PON-aryl) activities were measured spectrophotometrically.', 'Serological HBV tests and HBV DNA showed chronic HBV (precore mutant G1896A) in the diseased mothers whereas anti-HBc and anti-HBe were detected in their neonates. Liver function parameters were found normal in controls and both groups of newborns. Moderately increased transaminase levels were measured in HBV mothers, whereas TAC levels were decreased in hepatic mothers and their newborns. Interestingly albumin levels did not differ among the studied groups. PON 1 and PON-aryl activities in the diseased mothers (148+/-14 U/mL/min, 130+/-16 KU/mL/min) and their infants (32+/-6 U/mL/min, 24+/-5 KU/mL/min) were significantly lower as compared to those of control mothers (217+/-16 U/mL/min, 196+/-14 KU/mL/min p<0.001) and their newborns (57+/-6 U/mL/min, 48+/-8 UK mL/min p<0.001). Inverse significant correlations were found between the studied enzyme activities and liver enzymes in all the groups of study except in infants born from HBV mothers and positive with TAC in all the studied groups.'] Is maternal chronic hepatitis B virus implicated with low neonatal paraoxonase/arylesterase activities?