The cervical microbiota of Hispanics living in Puerto Rico is highly volatile and dominated by L. iners regardless of HPV status

IntroductionThe cervicovaginal microbiota is influenced by host physiology, immunology, lifestyle, and ethnicity. We hypothesized that there would be differences in the cervicovaginal microbiota among pregnant, non-pregnant and menopausal women living in Puerto Rico with and without Human Papillomavirus (HPV) infection and cervical cancer. We specifically wanted to determine if the microbiota associated with variation in cervical cytology. A total of 294 women comprised of reproductive-age non-pregnant (N=196), pregnant (N=37), and menopausal (N=61) women were enrolled. The cervicovaginal bacteria was characterized by 16S rRNA amplicon sequencing, the HPV were genotyped with SPF10-LiPA, and cervical cytology was quantified. High-risk HPV (HR-HPV, 67.3%) was prevalent, including genotypes not covered by the 9vt HPV vaccine. Cervical lesions (34%) were also common. The cervical microbiota was dominated by Lactobacillus iners. Pregnant women in the 2nd and 3rd trimesters had decreased diversity and a decreased abundance of microbes associated with bacterial vaginosis. Women in menopause had greater alpha diversity, a greater proportion of facultative and strictly anaerobic bacteria, and higher cervicovaginal pH than pre-menopausal women. Cervical lesions were associated with greater alpha diversity. However, no significant associations between the microbiota and HPV infection (HR or LR-HPV types) were found. The cervicovaginal microbiota women living in Puerto Rican were either dominated by L. iners or diverse microbial communities regardless of a womans physiological stage. We postulate that the microbiota and the high prevalence of HR-HPV, increase the risk of cervical lesions of women living in Puerto Rico.