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Public Health Rep. 1996 Mar-Apr; 111(2): 104–113.
PMCID: PMC1381713

Racial disparities in preterm births. The role of urogenital infections.


OBJECTIVES: To evaluate the impact of urogenital infections on the racial gap between black and white women in preterm birth rates. METHODS: A computer-assisted search of the medical literature was conducted through MEDLINE aided by a manual bibliographic search of published articles and relevant books. Estimates of the relative risk for preterm birth were extracted from published studies for the following infections: N. gonorrhea, syphilis, trichomoniasis, Chlamydia trachomatis, Group B streptococcal vaginal colonization, asymptomatic bacteriuria, genital mycoplasmas, and bacterial vaginosis. Estimates of the prevalence among black and white women by race for each of these infections were extracted from published studies. The attributable risk for preterm birth for selected infections was then calculated for the black and white populations and the impact on the racial gap in preterm births was estimated. RESULTS: Only bacterial vaginosis and bacteriuria appear to be established risk factors for preterm births. Significantly higher rates of bacterial vaginosis among black women may account for nearly 30% of the racial gap in preterm births. Higher rates of bacteriuria among black women may account for roughly 5% of the gap. CONCLUSION: Although these findings are limited by the reliability of published estimates of prevalence and relative risk for these infections, treatment of infections during pregnancy, particularly bacterial vaginosis, offers hope for reducing the racial gap in preterm births.

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