Sexually Transmitted Infection Risk Reduction Strategies Among US Adolescents and Adults With Multiple Opposite-Sex Sex Partners or Perceived Partner Nonmonogamy, 2011–2017

BACKGROUND: This study examined condom use and sexually transmitted infection (STI) testing among unmarried, non-cohabiting women and men who had multiple past-year partnerships or perceived their partner's involvement in another sexual relationship. METHODS: We identified 5868 and 5330 unmarried, non-cohabiting sexually active women and men aged 15 to 44 years using National Survey of Family Growth data for 2011 to 2017. To measure multiple partnerships, we created 4 dichotomous variables that included both past-year number of opposite-sex sex partners (1, 2 or more) and perceived partner nonmonogamy (PPNM) (yes, no). Results were stratified by relationship type at last sex ("steady" vs "casual"). RESULTS: Overall, 39.4% of women and 48.3% of men reported multiple partnerships and 23.4% and 24.0% reported PPNM. Lower condom use was seen for women and men who had 2 or more partners in the past year and PPNM than those with only 1 partner and no PPNM (women, 28.5%; 95% confidence interval CI, 24.1-32.9 vs 39.3%; 95% CI, 36.6-41.9) (men, 37.7%; 33.5-41.8 vs 54.9%; 51.9-57.9). STI testing was higher for groups with PPNM. Men with a steady sex partner had higher prevalence of past-year STI testing if they reported PPNM than not (adjusted prevalence ratio, 2.00; 95% CI, 1.63-2.45). CONCLUSIONS: Screening practices that include a standardized sexual risk assessment could identify those with multiple sex partners or PPNM and improve linkage to STI services. Availability of point-of-care tests and expedited partner therapy could provide targeted strategies that prioritize rapid diagnosis and effective partner treatment which may prevent further STI spread.