JACKSONVILLE, FLA. — Prevalence of bacterial vaginosis varies significantly by race/ethnicity in the United States, according to a large, nationally representative study from researchers at the Centers for Disease Control and Prevention.
As in previous studies, douching behavior was also significantly associated with bacterial vaginosis (BV). Lower education level, poverty, smoking, higher body mass index, and a history of pregnancy were associated with BV, but not significantly, Dr. Emilia Koumans said at a conference on STD prevention sponsored by the CDC.
BV is the most common cause of vaginal complaints among reproductive-age women. The condition increases the risk of acquiring HIV and sexually transmitted diseases. In pregnant women, BV infection increases the risk of miscarriage, chorioamnionitis, preterm labor, and preterm delivery.
Most of the 1,999 participants in the study were asymptomatic. There are few data to support treatment of asymptomatic women to reduce associated risks, Dr. Koumans said in response to an attendee question.
“There are studies underway to assess if chronic treatment of BV reduces risk of STD acquisition. It is difficult … to convince asymptomatic women of the need to continue using medication,” said Dr. Koumans, a medical officer in the division of STD prevention at the CDC.
Using 2001–2002 data from the National Health and Nutrition Examination Survey (NHANES), Dr. Koumans and her associates assessed self-collected vaginal swabs from 14- to 49-year-old females. The researchers determined pH, performed gram stains, and scored slides according to quantity of lactobacilli.
Overall prevalence of BV was 27%, and there were statistically significant differences according to race/ethnicity. “Non-Hispanic black women were disproportionately affected by BV,” Dr. Koumans said. Prevalence was 22% among whites, 29% among Mexican Americans, and 50% among blacks. “With further research, we hope to understand the cause or causes of BV and reasons for racial disparities,” she said.
BV prevalence did not vary by current pregnancy status, but women who had ever been pregnant and those who gave birth to a preterm baby showed a trend toward more BV, Dr. Koumans said.
Number of lifetime sex partners, age at first sex, and ever had sex with another woman were factors associated with increased prevalence of BV in univariate analyses. In a multivariate analysis, douching, income level, and ever having been pregnant were significant factors.
Another meeting attendee asked if BV is considered a sexually transmitted disease. “We would need more evidence,” Dr. Koumans said.