Background: The 9-valent human papillomavirus (9vHPV) vaccine was introduced in China in 2018. This study was conducted to monitor the occurrence of new-onset autoimmune diseases (AIs) in Chinese women vaccinated with the 9vHPV vaccine and adverse pregnancy outcomes in infants born to mothers with inadvertent pregnancy exposure.
Research design and methods: Women who received the first dose of the 9vHPV vaccine at age 16-26 years in Ningbo between January 2019 and March 2021 were monitored in the Ningbo Regional Health Information Platform. New-onset cases of seven pre-specified AIs diagnosed within six months after vaccination were collected. Cases of stillbirth and 23 major congenital anomalies diagnosed within three months of birth in target infants were collected.
Results: A total of 102,670 doses of the 9vHPV vaccine were administered to 41,609 women who had received no other HPV vaccine. New-onset AIs were diagnosed in 36 women, comprising 21 Hashimoto's, 11 Graves', and 4 uveitis disease cases. Among 50 women with maternal vaccination exposure, no stillbirths were observed. One case of microtia was observed.
Conclusions: In this first post-marketing surveillance of the 9vHPV vaccine in China, no safety signals were identified when putting the results in context to published data.
Keywords: 9-valent human papillomavirus vaccine; autoimmune diseases; post-marketing; pregnancy; product surveillance; safety.