Background: The marked racial disparity in sexually transmitted infection (STI) rates in the United States remains inadequately explained. One important factor may be concurrent sexual partnerships (relationships that overlap in time), which can transmit STIs more rapidly through a population than does sequential monogamy.
Methods: To determine prevalence, distribution, and correlates of U.S. women's involvement in concurrent partnerships, we analyzed sexual partnership data reported by the 10,847 women, age 15-44 years, in the 1995 National Survey of Family Growth. Overlapping sexual partnership dates were determined by computer program and visual review of the data.
Results: Prevalence of concurrent partnerships since January 1991 was 12% overall. Prevalence was lowest among currently married respondents (4%) and highest among those who were formerly married (22%), never married (19%), in the lowest income stratum (17%), age 18-24 years when interviewed (23%), or who first had sexual intercourse at age 12 or 13 (35%). Prevalence was 21% among blacks, 11% among whites, 8% among Hispanics, and 6% among Asian American and Pacific Islanders. Multiple logistic analysis substantially weakened the relationship between concurrency and black race (OR = 1.2; 95% CI = 1.1-1.4).
Conclusions: Marital status in particular is strongly related to concurrency; thus, lower marriage rates among blacks and the associated higher concurrency of sexual partners may contribute to racial disparities in STI rates.