中文摘要：

目的了解北京市男男性行为者的异性性行为特征及其影响因素。方法于2006年11月～2007年2月，在北京市招募男男性行为者进行问卷调查，了解其社会人口学和高危性行为特征。结果47．1％（255／541）的人曾与女性发生过性行为，在多因素Cox比例风险模型中，文化程度低（HR=1．98，95％CI=1．54～2．56）；性行为方式以异性为主（HR=2．92，95％CI=2．06～4．15）；与男男性行为者首次异性性行为的发生差异有统计学意义。13．9％（75／541）的人近3个月与女性发生过性行为，多因素Logistic回归分析结果显示，年龄〉26岁（OR=2．0，95％CI=1．12～3．56）、性行为方式以异性为主（OR=24．2，95％CI=11．1～52．6）和近1个月喝醉过（OR=2．6，95％CI=1．3～5．0）与男男性行为者近3个月发生异性性行为的关系差异有统计学意义。结论应采取相应措施控制人类免疫缺陷病毒（HIV）从男男性行为者向其女性性伴扩散。

英文摘要：

Objective To study the factors associated with characteristics of heterosexual intercourse among men who have sex with men （MSM） in Beijng. Methods Between November 2006 and February 2007, MSM were investigated to collect their socio - demographics and high risk sexual behaviors. Results 47.1% （255/541） of the MSM had sex with female. In the multivariate Cox proportion hazard regression model, education（ FIR = 1.98, 95 % CI = 1.54-2.56） and sexual orientation（HR = 2.92, 95 % CI = 2.06 -4.15） were the factors independently associated with the first heterosexual intercourse. 13.9 96 （75/541） of the MSM had sex with female in the past 3 months. Multiple logistic regression demonstrated that age 〉 26 （ OR = 2.0, 95 % CI 1.12, 3.56）, sexual orientation （ OR = 24.2, 95 % CI = 11.1 - 52.6）, and drunkeness in the last month （ OR = 2.6, 95 % CI = 1.3 - 5.0） had significant statistic significance. Conclusion Intervention measures should be taken to stop HIV spreading from MSM to normal females.