Moore KR, et al. - For the very first time, the relationship was examined between bacterial vaginosis (BV) and fibroids prospectively. A positive association between BV and the risk of developing fibroids was observed, but the timing of BV could be important. Moreover, BV was correlated with developing more than a single fibroid, consistent with the previous cross-sectional analysis of this same population.

• Transvaginal ultrasound results and self-reported questionnaire data were used from participants in the ongoing National Institute of Environmental Health Sciences (NIEHS) Study of Environment, Lifestyle & Fibroids (SELF) described previously.
• Starting in 2010, the study enrolled a volunteer sample of 1,695 African-American women ages 23-34 living in the Detroit, Michigan area.
• For 5 years, follow-up visits continued approximately every 20 months.
• If women had previously been diagnosed with fibroids ; had a hysterectomy; had ever taken medication to treat lupus, Grave's disease, Sjogren's scleroderma, or multiple sclerosis; or ever had any type of cancer treated with radiation or chemotherapy, they were considered to be ineligible.
• 22% of participants had fibroids at enrollment ultrasound screening.
• The follow-up analysis was performed among women who did not have a fibroid detected at enrollment and those who completed both baseline and follow-up 1 data collection.
• Between baseline and follow-up 1, the median interval was 19 months (interquartile range (IQR): 18-20 months).
• Women who had a birth during the interval because birth has been shown to be protective of fibroids, most likely due to postpartum uterine remodeling were excluded.
• Fibroids were evaluated by study sonographers as described previously using transvaginal ultrasound, the standard procedure for the detection and diagnosis of fibroids.
• They considered participants with ≥1 fibroid ≥0.5 cm at the follow-up 1 visit ultrasound to have incident fibroids.

• 660 were excluded (384 had a fibroid at enrollment, 1 was missing baseline BV data, 179 did not attend the follow-up visit, and 96 had a birth during the interval) among 1,695 enrolled women, leaving 1,035 eligible participants.
• At baseline, 37% (n=385) reported a history of BV.
• Since first BV diagnosis, the median time was 6 years (IQR: 3-9 years).
• At ultrasound screening, 10% (n=103) of women had fibroids discovered, 78% of whom had a single fibroid.