Correlates of Heterosexual Anal Intercourse among Women in the 2006-2010 National Survey of Family Growth.

INTRODUCTION: Heterosexual anal intercourse (HAI) is common among U.S. women. Receptive anal intercourse is a known risk factor for HIV, yet there is a paucity of data on HAI frequency and distribution in the United States. Condom use is lower with HAI vs. vaginal intercourse, but little is known regarding of correlates of HAI with and without condoms.

AIMS: The aims of this study were to describe recent (past 12 months) and lifetime HAI among sexually active reproductive-aged U.S. women, and to characterize women who engage in HAI with and without condoms.

METHODS: We analyzed a sample of 10,463 heterosexually active women aged 15-44 years for whom anal intercourse data were available in the 2006-2010 National Survey of Family Growth.

MAIN OUTCOME MEASURES: Weighted bivariate and multivariable analyses were used to determine HAI prevalence and correlates. Primary outcomes were lifetime HAI, recent (last 12 months) HAI, and condom use at last HAI.

RESULTS: In our sample, 13.2% of women had engaged in recent HAI and 36.3% in lifetime HAI. Women of all racial and ethnic backgrounds and religions reported recent anal intercourse. Condom use was more common at last vaginal intercourse than at last anal intercourse (28% vs. 16.4%, P < 0.001). In multivariable analysis, correlates of recent HAI included: less frequent church attendance, younger age at first intercourse, multiple sexual partners, history of oral intercourse, history of unintended pregnancy, and treatment for sexually transmitted infections (all P < 0.05). Correlates of lifetime HAI were similar, with the addition of older age, higher education, higher income, and history of drug use (all P < 0.05).

CONCLUSION: Women of all ages and ethnicities engage in HAI, at rates higher than providers might realize. Condom use is significantly lower for HAI vs. vaginal intercourse, putting these women at risk for acquisition of sexually transmitted infections.