Analysis and prediction of trends in birth population and HBsAg-positive pregnant women in Zaozhuang City, 2012-2024.

INTRODUCTION

To analyze trends and project future changes in birth population and HBsAg-positive pregnant women in Zaozhuang City from 2012 to 2024, providing baseline data and evidence for optimizing resource allocation and formulating strategies to eliminate mother-to-child transmission (MTCT) of hepatitis B virus (HBV).

METHODS

Data on annual births and HBsAg-positive pregnant women were col from the Zaozhuang Statistical Yearbook and the Shandong Provincial Immunization Program Information System (2012 -2024). Birth rate and maternal HBsAg prevalence were calculated. Trends were analyzed using Joinpoint regression to estimate annual percent change (APC) and average annual percent change (AAPC). Curve regression models were fitted to project 2025 levels. Time series analysis based on monthly data was performed for forecasting.

RESULTS

The birth rate declined significantly overall (AAPC = -6.676%, p = 0.015), ranging from 5.989‰ to 17.383‰ during 2012 -2024. A period of rapid decline occurred from 2017 to 2021 (APC = -18.730%, p = 0.018). The mean maternal HBsAg prevalence was 2.896%. A significant decreasing trend was observed from 2015 to 2024 (APC = -4.442%, p = 0.001). The birth rate and maternal HBsAg prevalence were best fitted by exponential and quadratic function models, respectively, yielding 2025 projections of 5.876‰ and 1.755%. ARIMA models were selected as optifor forecasting monthly time series: ARIMA(0,1,0)(0,1,2)₁₂ for birth count and ARIMA(0,1,1)(1,1,1)₁₂ for HBsAg-positive pregnant women count.

CONCLUSION

Fertility levels and maternal HBsAg prevalence in Zaozhuang City exhibit sustained declining trends. The fitted model can be used for short-term prediction, providing robust evidence to inform regional healthcare resource planning and the development of comprehensive interventions to eliminate HBV MTCT.