Meeting Paper
IDSOG Paper
Impact of contraceptive initiation on vaginal microbiota

Presented in part at the annual meeting of the Infectious Diseases Society for Obstetrics and Gynecology, Park City, UT, Aug. 10-12, 2017.
https://doi.org/10.1016/j.ajog.2018.02.017Get rights and content
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open access

Background

Data evaluating the impact of contraceptives on the vaginal microbiome are limited and inconsistent.

Objective

We hypothesized that women initiating copper intrauterine device use would have increased bacterial vaginosis and bacterial vaginosis-associated microbes with use compared to women initiating and using hormonal contraceptive methods.

Study Design

Vaginal swabs (N = 1047 from 266 participants seeking contraception) for Nugent score determination of bacterial vaginosis and quantitative polymerase chain reaction analyses for assessment of specific microbiota were collected from asymptomatic, healthy women aged 18-35 years in Harare, Zimbabwe, who were confirmed to be free of nonstudy hormones by mass spectrometry at each visit. Contraception was initiated with an injectable (depot medroxyprogesterone acetate [n = 41], norethisterone enanthate [n = 44], or medroxyprogesterone acetate and ethinyl estradiol [n = 40]), implant (levonorgestrel [n = 45] or etonogestrel [n = 48]), or copper intrauterine device (n = 48) and repeat vaginal swabs were collected after 30, 90, and 180 days of continuous use. Self-reported condom use was similar across all arms at baseline. Quantitative polymerase chain reaction was used to detect Lactobacillus crispatus, L jensenii, L gasseri/johnsonii group, L vaginalis, L iners, Gardnerella vaginalis, Atopobium vaginae, and Megasphaera-like bacterium phylotype I from swabs. Modified Poisson regression and mixed effects linear models were used to compare marginal prevalence and mean difference in quantity (expressed as gene copies/swab) prior to and during contraceptive use.

Results

Bacterial vaginosis prevalence increased in women initiating copper intrauterine devices from 27% at baseline, 35% at 30 days, 40% at 90 days, and 49% at 180 days (P = .005 compared to marginal prevalence at enrollment). Women initiating hormonal methods had no change in bacterial vaginosis prevalence over 180 days. The mean increase in Nugent score was 1.2 (95% confidence interval, 0.5–2.0; P = .001) in women using copper intrauterine devices. Although the frequency and density of beneficial lactobacilli did not change among intrauterine device users over 6 months, there was an increase in the log concentration of G vaginalis (4.7, 5.2, 5.8, 5.9; P = .046) and A vaginae (3.0, 3.8, 4.6, 5.1; P = .002) between baseline and 30, 90, and 180 days after initiation. Among other contraceptive groups, women using depot medroxyprogesterone acetate had decreased L iners (mean decrease log concentration = 0.8; 95% confidence interval, 0.3–1.5; P = .004) and there were no significant changes in beneficial Lactobacillus species over 180 days regardless of contraceptive method used.

Conclusion

Copper intrauterine device use may increase colonization by bacterial vaginosis–associated microbiota, resulting in increased prevalence of bacterial vaginosis. Use of most hormonal contraception does not alter vaginal microbiota.

Key words

bacterial vaginosis
hormonal contraception
intrauterine device
lactobacilli
vaginal microbiota

Cited by (0)

Supported by the Bill and Melinda Gates Foundation (OPP1055833). The funding source had no role in study design, collection, analysis, or interpretation of data; writing of the article; or decision to submit for publication.

Disclosure: S.L.A., and S.L.H. are consultants for Merck, Whitehouse Station, NJ. S.L.H. is a consultant for Symbiomix, Newark, NJ; Biofire Diagnostics, Salt Lake City, UT; and Hennepin Life Sciences, Minneapolis, MN; and receives research funding from Becton Dickinson, Franklin Lakes, NJ; and Cepheid, Sunnyvale, CA. The remaining authors report no conflicts of interest.

Cite this article as: Achilles SL, Austin MN, Meyn LA, et al. Impact of contraceptive initiation on vaginal microbiota. Am J Obstet Gynecol 2018;218:622.e1-10.