Objectives: To describe heterosexual anal sex activity during a year and to identify factors associated with heterosexual anal sex and condom use during anal sex.
Methods: Secondary analysis of data from a trial conducted in 3 public sexually transmitted disease (STD) clinics. Patients described sexual behaviors every 3-months for the year. Logistic regression models with generalized estimating equations were used to include multiple observations for each subject.
Results: Two thousand three hundred fifty-seven heterosexual subjects reported on 6611 3-month intervals that included 9235 partnerships. About 18.3% of subjects had anal sex in a particular 3-month interval and 39.3% in the year. About 23.5% of subjects had anal sex in at least two 3-month intervals in the year. Anal sex was associated with having more sex acts, 2 or more sex partners, unprotected vaginal sex, and a main partner. For anal sex in the past 3 months, 27.3% of subjects consistently used condoms, and 63% of subjects never used condoms. Consistent condom use for anal sex was associated with having consistent condom use for vaginal sex, 2 or more partners, and anal sex with casual or new partner.
Conclusion: STD clinic patients were commonly engaged in heterosexual anal sex, and most of them never used condoms during anal sex. Patients who had anal sex tended to also engage in other risk behaviors that put them at risk of STD/human immunodeficiency virus. Clinicians should ask about anal sex, appropriately examine and test patients who have had anal sex, and recommend condom use for both anal and vaginal sex.