Partner age difference and prevalence of chlamydial infection among young adult women.

OBJECTIVES: Sexual partner mixing by age is common among adolescents and adults. Although adolescent girls with older male partners are at increased risk of sexually transmitted infection, the importance of this association in young adults is unclear.

GOAL: To assess the association between partner age difference and prevalence of chlamydial infection among young women.

STUDY DESIGN: Using Wave III of the National Longitudinal Study of Adolescent Health (April 2, 2001-May 9, 2002), the authors examined the relation between the prevalence of chlamydial infection and the partner age among women aged 18 to 26 years.

RESULTS: Among women with most recent partners 2 to 8 years younger, the odds of chlamydial infection were approximately 2 times greater [adjusted odds ratio (OR), 1.8; 95% confidence interval (CI), 0.9, 3.5] than among women with partners within 1-year age difference, adjusting for number of partners in the past year. Prevalence of chlamydial infection was only slightly greater for women with partners 2 to 5 years older (adjusted OR, 1.4; 95% CI, 0.9, 2.3) and partners 6 or more years older (adjusted OR, 1.6; 95% CI, 0.9, 2.8), when compared with women with partners within 1-year age difference. The relation between most discordant partner age difference and chlamydial infection seems to vary by women's race/ethnicity, although these stratified estimates are imprecise.

CONCLUSIONS: These findings suggest that among young adult women, in contrast to adolescents, older male partners are only moderately associated with the prevalence of chlamydial infection. Young adult women have the lowest odds of infection with partners within 1 year of age difference.