Vaginal microbiome changes with levonorgestrel intrauterine system placement

Area of Science:

• Microbiology
• Gynecology
• Reproductive Health

Background:

• The female genital tract harbors a complex microbiome crucial for reproductive health.
• Intrauterine devices (IUDs) are a common form of contraception, and understanding their impact on the local microbiome is important.

Purpose of the Study:

• To investigate alterations in the bacterial ecology of the female genital tract associated with the use of the levonorgestrel intrauterine system (LNG IUS).

Main Methods:

• Vaginal, cervical, and uterine samples were collected from 11 regularly cycling women at multiple time points before and after LNG IUS insertion.
• Bacterial species were identified using DNA sequencing and analysis of over 6 million reads.
• Replicate samples were used to ensure consistency in collection and processing.

Main Results:

• Lactobacillus crispatus was the most prevalent bacterial species, constituting 48.9% of all identified bacteria.
• Vaginal microbiome composition showed high consistency between replicate samples and between vaginal and cervical samples.
• A statistically significant increase in L. crispatus dominance (>50% of reads) was observed after LNG IUS insertion (OR 2.13).
• Burkholderia, a bacterial genus often associated with environmental contamination, was prevalent in uterine samples both before and after LNG IUS placement.

Conclusions:

• The vaginal microbiome demonstrates minimal changes in response to the placement of the levonorgestrel intrauterine system (LNG IUS).
• No clinically significant differences in the vaginal microbiome were detected following LNG IUS insertion.
• Further research is warranted to correlate these microbiome findings with clinical outcomes.