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Bacterial vaginal flora in relation to changing oestrogen levels.
J D Wilson1, R A Lee, A H Balen
1Department of Genitourinary Medicine, The General Infirmary at Leeds, UK. janet_d.wilson@leedsth.nhs.uk
International Journal of STD & AIDS
|May 26, 2007
Summary
Hormonal changes, particularly oestradiol levels, influence bacterial vaginosis (BV). Higher oestradiol is linked to normal vaginal flora, while lower levels, seen in smokers, correlate with increased BV risk.
Area of Science:
- Reproductive Endocrinology
- Microbiome Research
- Women's Health
Background:
- Bacterial vaginosis (BV) is a common vaginal condition.
- Hormonal fluctuations are suspected to play a role in BV development and resolution.
Purpose of the Study:
- To investigate the relationship between serum oestradiol levels and vaginal flora composition.
- To assess the impact of hormonal treatment on vaginal flora and oestradiol levels.
Main Methods:
- Studied vaginal flora and serum oestradiol in 55 women at baseline and during hormonal treatment.
- Compared oestradiol levels between women with and without BV.
- Analyzed oestradiol changes in relation to flora improvement or worsening.
Main Results:
- Normal vaginal flora increased from 69% to 91% after hormonal treatment.
- Mean oestradiol was significantly lower in women with BV (39.07 ng/L) versus normal flora (176.41 ng/L).
- Smokers had lower mean oestradiol levels (118.67 ng/L) than non-smokers (173.95 ng/L).
- A rise in oestradiol correlated with improved vaginal flora, with greater increases associated with reversion from BV.
Conclusions:
- Hormonal factors, specifically oestradiol, appear to influence the natural history of bacterial vaginosis.
- Lower oestradiol levels may contribute to the increased risk of BV observed in smokers.
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