The changing trend of hepatitis B virus carrier rate with different combinations of hepatitis B virus markers and their impact on maternal perinatal characteristics and pregnancy outcomes: A multicenter retrospective cohort study

Background Understanding the prevalence of Hepatitis B Virus (HBV) markers in pregnant women, and their impact on perinatal outcomes is imperative to reach global elimination targets- this can help risk stratify women for early treatment and more intensive monitoring. Therefore, it is particularly important to explore the trends in the prevalence of HBV under different combinations of HBV markers and their impact on the characteristics of pregnant women during the perinatal period and the outcomes of pregnancy. Methods This is a multicenter retrospective cohort studywas conducted in October 2024 to analyze the involving 110,827 pregnant women treated in Hangzhou, China, from 2015 to 2022. Of these, 5,331 cases were identified as HBsAg carriers, and 105,496 cases were non-HBsAg carriers. The cohort was divided into two parallel groups: HBeAg positive, consisting of 1087 cases, and HBeAg negative, comprising 4244 cases. Regarding the HbsAg negative group, This cohort was further categorized based on the complete pattern of their Hepatitis B virus (HBV) serological markers. Specifically, 46289 pregnant women tested negative for all HBV markers, indicating no evidence of HBV infection. Additionally, 1242 pregnant women exhibited positive or negative results for Hepatitis B core antibody (HBcAb) and other HBV markers, which may suggest a history of infection or post-vaccination status. Finally, 57965 HbsAg negative pregnant women demonstrated positive Hepatitis B surface antibody (HBsAb), typically indicating immunity to HBV, likely due to recovery from past infection or vaccination. The chi-squared test was used to compare the composition ratios of a series of maternal characteristics among the different groups of pregnant women. Multivariate logistic regression analysis, adjusted Odds Ratio (aOR), and 95% confidence interval (CIs) were also used to evaluate the impact of different HBV carrier states on key perinatal variables. Results The HBsAg positive carrier rate among pregnant women in Hangzhou City was 4.81%, 95%CI(4.70%-4.90%). The risk of the HBsAg positive group increased with maternal age, with aOR ranging from 0.684, 95%CI (0.450–1.038) to 1.916, 95%CI (1.537–2.388),The risk of hepatitis B virus in the HBeAg positive group weakened with increasing maternal age, with a aOR ranging from 0.597, 95%CI (0.478–0.744) to 0.207, 95%CI (0.108–0.397). HBcAb positive (+/- other markers) group increased with maternal age, with aOR ranging from 1.262, 95%CI (1.211–1.315) to 1.452, 95%CI (1.293–1.632). The HBsAg carrier rate among floating populations varied as follows: Non Zhejiang Province > Zhejiang but not Hangzhou > Hangzhou (aOR = 1.282, 1.253 vs. 1). Furthermore, the HBV carrier rate followed an upwards trend with increasing gravidity. Pregnant women who were HBsAg and HBeAg carriers were more likely to have concurrent intrahepatic cholestasis of pregnancy (ICP, aOR = 3.401, 95%CI(2.974–3.890) and 1.155, 95%CI (0.855–1.561), and less likely to develop hyperlipidemia, HBsAg positive group (0.624, 95%CI (0.521–0.748). Conclusion The HBV carrier rate varies among different combinations of maternal serological markers and leads to distinct maternal perinatal characteristics and pregnancy outcomes.