Comparison of hepatitis B viral loads and viral antigen levels in child-bearing age women with and without pregnancy

Background Pregnancy is a unique physiological condition with the cellular immune functions compromised at some extents to allow the mature of growing fetus. Whether pregnancy may influence the replication of hepatitis B virus (HBV) is less studied. The present study aimed to investigate the influence of pregnancy on the replication of HBV and expression of viral antigens by comparing the levels of HBV DNA and viral antigens in pregnant and non-pregnant women. Methods A total of 727 HBsAg-positive serum samples, collected from 214 pregnant women and 513 non-pregnant women of childbearing age, were included. Based on the pregnancy status, subjects were divided into four groups: nulliparous ( n = 158), pregnant ( n = 214), 7–12 months postpartum ( n = 170), and 2–5 years postpartum ( n = 185). The levels of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) were quantitatively measured with microparticle enzyme immunoassay. HBV DNA levels were detected by fluorescent real-time PCR. Results The median ages of four groups were 25.0, 25.3, 26.2 and 29.3 years, respectively ( p < 0.01). HBeAg-positive proportions were 34.2, 33.6, 35.3 and 29.2%, respectively ( p = 0.624). HBV DNA levels in HBeAg-positive women were higher than those in HBeAg-negative women (7.88 vs 2.62 log IU/ml, p < 0.001). HBV DNA levels in the four groups with positive HBeAg were 7.8, 7.7, 8.0 and 8.0 log IU/ml, respectively ( p = 0.057), while HBsAg titers were 4.4, 4.5, 4.6 and 4.8 log IU/ml ( p = 0.086) and HBeAg titers were 3.1, 3.0, 3.1 and 3.0 log S/CO ( p = 0.198). In the four groups with negative HBeAg, HBV DNA levels were 2.3, 2.6, 2.5 and 2.8 log IU/ml, respectively ( p = 0.085), while HBsAg titers were 3.1, 3.3, 3.3 and 3.0 log IU/ml ( p = 0.06). Conclusions Serum levels of HBV DNA and viral antigens showed no significant changes in nulliparous, pregnant, and postpartum women, regardless of the HBeAg status. The results indicate that pregnancy has little influence on the replication of HBV and the expression of viral antigens.