# Karolinska Institutet HPV vaccine pregnancy study

> Live situation record from CLSTR: https://clstr.news/situations/karolinska-institutet-hpv-vaccine-pregnancy-study
> Updated: 2026-10-07T22:50:12.000Z. Sources: 3. Developments: 2.

Researchers at Karolinska Institutet have published findings regarding the impact of the human papillomavirus (HPV) vaccine on pregnancy outcomes. 

Based on an analysis of Swedish registry data involving over 624,000 pregnancies among first-time mothers, the study indicates that women vaccinated with the quadrivalent HPV vaccine prior to pregnancy may face a lower risk of childbirth complications. Specifically, vaccinated women showed a roughly 5 percent lower risk of preterm birth and a 15 percent lower risk of very preterm birth compared to unvaccinated women. The researchers noted that this association appeared stronger in women who received the vaccine before age 17. While the study is observational and cannot definitively establish a causal link, the authors emphasized the significance of the large sample size and long duration of the research.

## Timeline

### 2026-10-07: Karolinska Institutet study links HPV vaccine to lower preterm birth risk

A Karolinska Institutet study suggests HPV vaccination before pregnancy is linked to a lower risk of preterm birth and other pregnancy complications.

2 sources. https://clstr.news/cluster/karolinska-institutet-study-links-hpv-vaccine-to-lower-preterm-birth-risk

### 2026-09-23: Karolinska Institutet study links probiotics to lower mortality in preterm infants

A Karolinska Institutet study of nearly 4,700 infants suggests probiotics are linked to lower risks of death and necrotizing enterocolitis in very preterm babies.

2 sources. https://clstr.news/cluster/karolinska-institutet-study-links-probiotics-to-lower-mortality-in-preterm-infants

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Cite as: Karolinska Institutet HPV vaccine pregnancy study. CLSTR, https://clstr.news/situations/karolinska-institutet-hpv-vaccine-pregnancy-study