SEXUAL-BEHAVIOR AND VAGINAL COLONIZATION BY GROUP-B STREPTOCOCCUS AMONG MINORITY WOMEN

Objective: To test the hypothesis that sexual behaviors predict coloni zation of the vagina by group B streptococcus among minority women. Me thods: We conducted a prospective, descriptive study of 192 consecutiv e African-American (37%) and Hispanic women (63%). Each woman underwen t a detailed interview concerning sexual behavior. Separate specimens were taken from the endocervix, upper vagina, lower vagina, and anorec tum and placed in selective broth media for isolation of group B strep tococcus. Significant behavioral predictors of vaginal group B strepto coccus colonization and heavy (3-4+) colonization were identified usin g stepwise logistic regression. Results: The incidence of vaginal colo nization was 39% and heavy colonization was 35%. Nineteen percent repo rted anal intercourse, 46% reported sex at least two times per week, a nd 21% reported more than one partner in the previous 30 days. The sig nificant predictors of vaginal group B streptococcal infection were: A frican-American ethnicity, adjusted odds ratio (OR) 6.1 (95% confidenc e interval [CI] 2.5-15.1); presence of rectal group B streptococcus, a djusted OR 100.6 (95% CI 26.7-379.3); nulliparous, adjusted OR 3.6 (95 % CI 1.4-9.5); and nonpregnant status, adjusted OR 3.9 (95% CI 1.3-12. 2). The significant predictors of heavy colonization were: more than o ne partner in the last 30 days, adjusted OR 2.6 (95% CI 1.2-5.6); and African-American ethnicity, adjusted OR 2.3 (95% CI 1.2-4.5). Anal int ercourse was associated with a reduced likelihood of vaginal group B s treptococcal infection, adjusted OR 0.34 (95% CI 0.12-0.91). Conclusio n: Sexual behavior, especially anal intercourse, does not predict vagi nal colonization by group B streptococcus. African-American women are more likely to have vaginal and heavy group B streptococcus colonizati on. Heavy vaginal colonization is associated with multiple partners in African-American women.