The impact of human papillomavirus (HPV) vaccination on the risk of adverse obstetric outcomes: a data linkage study.

Background: Human papillomavirus (HPV) vaccination has reduced rates of cervical cancer. Research suggests that women with HPV, precancerous disease, and prior invasive treatments are at increased risk of preterm birth. This study aimed to determine if there is a reduction in adverse obstetric outcomes for HPV vaccinated women.

Methods: This was a cohort study including data linkage of routinely collected pregnancy data, HPV vaccine status, colposcopy, histology diagnosis and subsequent cervical treatment for all women in Aberdeen, United Kingdom. The exposure was HPV vaccination. The association between adverse obstetric outcomes and HPV vaccination status were analysed using a generalised estimation equations (GEE) model. Spontaneous preterm birth (sPTB), low birth weight (LBW) and pre-labour preterm rupture of membranes (PPROM) were the primary outcomes.

Findings: 9200 women (11174 spontaneous births) who had a pregnancy recorded within the Aberdeen, Scotland between 2006 and 2020 were included. There was no difference in sPTB according to HPV vaccination status [adjusted Odds Ratio (aOR) 1.00 (95 %CI 0.82 to1.22) p = 0.27]. Preterm prelabour rupture of membranes (PPROM) [aOR 0.52 (95 %CI 0.30 to 0.89); p = 0.03] and prelabour rupture of membranes at term (PROM) [aOR 0.25 (95 %CI 0.17 to 0.36); p < 0.01], pre-eclampsia [aOR 0.38 (0.28,0.51); p < 0.01] and antepartum haemorrhage (APH) [aOR 0.71 (0.59,0.85); p < 0.01] were significantly reduced in HPV-vaccinated women.

Interpretation: Spontaneous preterm birth rate was unchanged when comparing women who were and were not vaccinated against HPV in this population. Our data however does suggest that other obstetric outcomes including PPROM, PROM, pre-eclampsia and antepartum haemorrhage may be significantly reduced in women with HPV vaccination.