Karolinska Institutet study links HPV vaccine to lower preterm birth risk

Researchers at Karolinska Institutet have found that women vaccinated against the human papillomavirus (HPV) before pregnancy may face a lower risk of several pregnancy and childbirth complications. The study, published in The BMJ, specifically highlights a reduced risk of preterm birth.

Based on Swedish registry data, the study analyzed 624,713 pregnancies among first-time mothers aged 16 to 35 between 2006 and 2023. Of these, 92,620 women had received the quadrivalent HPV vaccine prior to pregnancy. Compared to unvaccinated women, those vaccinated showed a roughly 5 percent lower risk of preterm birth and a 15 percent lower risk of very preterm birth.

The findings suggest that the association is stronger among women who were vaccinated before the age of 17. While the researchers noted that the study is observational and cannot definitively establish a causal link, they emphasized the significance of the large sample size and long duration of the study.