OBJECTIVE  To investigate rubella virus (RuV) infection status and immune profiles among women of childbearing age in a three-A hospital in Sichuan, providing evidence for good and sound childrearing.

METHODS  A total of 13 790 women undergoing preconception examinations and 78 312 pregnant women receiving routine prenatal care at Sichuan Jinxin Xinan Women and Children Hospital from Jan. 2016 to Dec. 2024 were enrolled. The levels of RuV-specific immunoglobulin M (IgM) and IgG antibodies in the peripheral blood were analyzed in both groups.

RESULTS  The overall seropositivity rates of RuV-IgM and RuV-IgG among women of childbearing age were 1.33% and 80.40%, respectively. The preconceptional and pregnant groups showed RuV-IgM positivity rates of 1.73% and 1.26%, respectively, and RuV-IgG positivity rates of 81.71% and 80.17%, respectively. Significant differences (P＜0.05) were observed between the two groups regarding RuV-IgM positivity rate, IgG positivity rate, IgM+/IgG+, IgM-/IgG+ and IgM-/IgG-. From 2016 to 2024, both groups exhibited an upward trend in RuV-IgM positivity rate but declining trend in RuV-IgG positivity rate. The positive rate of RuV-IgG decreased to 77.63% in the preconceptional group by 2024, 76.17% in the pregnant group. Between 2016 and 2024, the proportions of IgM-/IgG- and IgM+/IgG+ cases in both groups increased annually, while the proportion of IgM-/IgG+ cases decreased. Pregnant women under the IgM-/IgG+ infection status demonstrated lower RuV-IgG antibody levels than preconception women (P＜0.05), and both groups showed declining RuV-IgG trends under IgM+/IgG+ and IgM-/IgG+ infection status.

CONCLUSIONS  Declining rubella immunity among women of childbearing age, particularly pregnant women, elevates infection risks. Strengthening RuV-specific antibody surveillance is crucial to enhance population immunity.