Effect of contraceptive methods on the vaginal microbiome and host immune factors.

OBJECTIVE

The objective of this study was to assess alterations in vaginal microbiota and immune markers over the first 3 months following initiation of copper intrauterine device (copper IUD), levonorgestrel (LNG) implant, and intramuscular depot medroxyprogestone acetate (DMPA-IM).

STUDY DESIGN

We included 162 participants from the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial, which enrolled healthy, HIV-negative women seeking contraception and randomized them to a copper IUD, LNG implant, or DMPA-IM. Microbiome and immune profiles in vaginal swab samples collected at enrollment, 1 month and 3 months were analyzed. We categorized microbiome profiles as ''optimal'', ''intermediate'', or ''non-optimal'' based on established criteria [1]. We compared microbiome and immune markers across contraceptive groups and evaluated changes to 1 and 3 months.

RESULTS

Copper IUD users had a more diverse vaginal microbiome and generally increased inflammatory cytokines and antimicrobial peptides over the 3-month follow-up, compared to LNG-implant and DMPA-IM users [2]. LNG-implant users had less complex vaginal microbiomes with reduced inflammation, while DMPA-IM showed little change in either microbiome composition or inflammatory markers. Copper IUD users exhibited lower microbiome stability and a higher likelihood of transitioning to less optimal profiles. In contrast, LNG-implant users showed greater stability and a higher probability of transition to optimal microbiome and immune marker profiles.

CONCLUSIONS

Contraceptive methods affect the vaginal microbiome differently. Copper IUD use may lead to less favorable profiles and increased levels of some immune markers, indicating potential adverse health effects. Conversely, LNG-implant usage promotes a more favorable microbiome and immune marker balance.

IMPLICATIONS

Our findings suggest that copper IUDs are associated with decreased prevalence of Lactobacillus-dominated microbiomes, higher transition rates towards less optimal microbiome and increased inflammatory profiles, which may lead to negative implications for gynecologic and reproductive health, the LNG-implant may offer positive health benefits with increased prevalence of L. crispatus-dominated microbiomes.