The impact of combined contraceptive vaginal ring on vaginal environment: an observational, longitudinal study.

Purpose: To assess the relationship between combined contraceptive vaginal ring (CVR) and vaginal microbiome using 16S rRNA gene sequencing.

Materials and methods: We enrolled 20 women for 8 weeks in an open-label study using CVR (NuvaRing^®) that delivered 15 mcg ethinylestradiol and 120 mcg etonogestrel daily. The vaginal microbiome was assessed at baseline and after 2 months by sequencing the 16S rRNA genes amplified from the total genomic DNA isolated from the sample.

Results: Bacterial distribution richness and equity did not significantly change after 2 months, and the dominant bacterial strain was Lactobacillus crispatus. Only one woman with a history of vestibulodynia and recurrent vulvovaginitis showed an increase in bacterial biodiversity, with a switch to the relative abundance of anaerobic bacteria.

Conclusions: Our results suggest that CVR does not adversely affect the composition and structure of the vaginal microbiome. However, special care should be taken in patients with a history of vestibulodynia and/or recurrent vulvovaginal infections.