Menu Close

Race/Ethnicity, Vaginal Flora Patterns, and pH during Pregnancy


Royce, Rachel A.; Jackson, Tracy P.; Thorp, John M., Jr.; Hillier, Sharon L.; Rabe, Lorna K.; Pastore, Lisa M.; & Savitz, David A. (1999). Race/Ethnicity, Vaginal Flora Patterns, and pH during Pregnancy. Sexually Transmitted Diseases, 26(2), 96-102.


Objectives: To investigate the relationship between bacterial vaginosis during pregnancy and black race/ethnicity.
Study design: Gram staining was used to evaluate vaginal flora in 842 women at 24 to 29 weeks' gestation.
Results: Overall, 22.3% of blacks and 8.5% of whites had bacterial vaginosis. Vaginal pH and flora differed significantly by race/ethnicity; blacks were more likely to have pH > or = 4.5, no lactobacilli, small gram-variable and -negative rods, and Mobiluncus compared with whites (odds ratios 1.6, 1.5, 1.4, and 10.6, respectively). Quantity of morphotypes also differed, especially for Mobiluncus. Among women with Mobiluncus present (12.0% of blacks and 1.3% of whites), 73.3% of blacks compared with 40.0% of whites had the highest level. Adjustment for sociodemographics, sexual activity, sexually transmitted diseases, health behavior, and sexual hygiene did not explain these differences.
Conclusion: We observed race/ethnicity differences in vaginal flora ecology. These differences may ultimately play a role in the larger proportion of preterm deliveries among black women compared with white women.


Reference Type

Journal Article

Year Published


Journal Title

Sexually Transmitted Diseases


Royce, Rachel A.
Jackson, Tracy P.
Thorp, John M., Jr.
Hillier, Sharon L.
Rabe, Lorna K.
Pastore, Lisa M.
Savitz, David A.