Comparative study of vulva and abdominal skin microbiota of healthy females with high and average BMI.

BACKGROUND: Obesity is known to modulate human health in a number of ways including altering the microbiome of the gut. Very few studies have examined the how obesity may affect the microbiomes of sites distant to the gut. We hypothesized that vulva and abdominal skin may be especially susceptible to body mass index (BMI)-induced alterations in biophysical properties and the microbiome due increased maceration and skin folds at those sites. The aim of this study was to determine if high BMI (≥30) was associated with alterations in the biophysical properties and microbiomes of vulva and abdominal skin.

RESULTS: The vulvar microbial communities of healthy reproductive-aged females were examined using 16S rRNA sequencing techniques. Our results show that vulvar pH of women with high body mass index (BMI) was statistically higher than that of women with average BMI. Phylogenetic analysis of the vulvar microbiota indicated that women with average BMI have a predominately Lactobacillus-dominated flora, whereas women with high BMI and higher pH were predominately colonized by Finegoldia and Corynebacterium. This BMI-associated shift in microbiota was not observed in samples collected from the exposed skin around the belly, indicating the effect is not global.

CONCLUSION: These results indicate that physiological changes associated with changes in BMI may modulate the vulva microbiome.