Abstract: Objective This research seeks to identify the determinants of postpartum hepatitis outbreaks in pregnant women with hepatitis B infection who are receiving treatment to prevent mother-to-child transmission based on the nomogram model. Methods A total of 136 pregnant women with chronic hepatitis B infection treated from January 2021 to January 2023, were selected as research subjects. All patients received mother-to-child transmission blockade therapy. General data of the patients were collected, and serum levels of Alanine Aminotransferase (ALT), HBV DNA, Hepatitis B Surface Antigen (HBsAg), Hepatitis B e Antigen (HBeAg), and Hepatitis B Core-related Antigen (HBcrAg) were measured before antiviral therapy. Following delivery, all mothers were followed up for 48 weeks. Based on the follow-up outcomes, they were divided into a flare group (n=31) and a non-flare group (n=105). Logistic regression analysis was used to screen for factors affecting postpartum hepatitis flares, a nomogram model was developed, and its fit was evaluated using calibration curves. Results In the flare group, pre-treatment serum levels of ALT, HBcrAg, HBsAg, HBeAg, and HBV DNA were (29.30 ± 2.71) U/L, (7.42 ± 1.03) log₁₀μg/mL, (4.25 ± 0.56) log₁₀IU/mL, (2.57 ± 0.42) log₁₀SCO, and (7.49 ± 1.12) log₁₀IU/mL (P<0.05). Multivariate analysis indicated that levels of ALT, HBcrAg, HBsAg, HBeAg, and HBV DNA were significant factors affecting postpartum hepatitis flare, with higher levels associated with an increased risk of flare (P<0.05). The calibration curve showed a mean absolute error of 0.026, indicating that the predictive model’s calibration curve approached the ideal curve. Conclusion ALT levels and hepatitis B virus markers can influence postpartum flares in pregnant women. Effective interventions based on these markers can reduce the risk of flare.

Key words: Chronic hepatitis B infection, Mother-to-child transmission blockade, Postpartum hepatitis flare, Risk factor analysis