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Race/ethnicity, vaginal flora patterns, and pH during pregnancy
R A Royce1, T P Jackson, J M Thorp
1Department of Epidemiology, School of Public Health, University of North Carolina at Chapel Hill 27599, USA. Rachel_Royce@unc.edu
Sexually Transmitted Diseases
|February 25, 1999
Summary
Black women have distinct vaginal flora during pregnancy, increasing bacterial vaginosis risk compared to white women. These microbial differences, particularly Mobiluncus, are not explained by lifestyle factors and may impact preterm birth rates.
Area of Science:
- Obstetrics and Gynecology
- Microbiology
- Racial Health Disparities
Background:
- Bacterial vaginosis (BV) is a common vaginal condition.
- Pregnancy-related BV is linked to adverse outcomes like preterm birth.
- Existing research suggests potential racial/ethnic disparities in BV prevalence.
Purpose of the Study:
- To examine the association between bacterial vaginosis (BV) and race/ethnicity in pregnant individuals.
- To investigate specific differences in vaginal flora composition between Black and White pregnant women.
Main Methods:
- A cohort of 842 pregnant women were assessed between 24 to 29 weeks' gestation.
- Vaginal flora was evaluated using Gram staining.
- Key indicators analyzed included vaginal pH, presence of lactobacilli, and specific morphotypes like Mobiluncus.
Main Results:
- Black women exhibited a higher prevalence of BV (22.3%) compared to White women (8.5%).
- Significant differences in vaginal pH and flora were observed, with Black women more likely to have higher pH, absence of lactobacilli, and presence of Mobiluncus.
- These disparities persisted after adjusting for sociodemographic factors, sexual behavior, and hygiene practices.
Conclusions:
- Race/ethnicity is associated with distinct vaginal flora ecology during pregnancy.
- Observed differences in vaginal microbiota may contribute to the higher rates of preterm birth among Black women.
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