Prevalence and Patterns of Extramarital Sex among Chinese Men and Women: 2000-2015.

Despite growing concern about the "sexual revolution" in China in the past decades, empirical evidence regarding the national trends in prevalence and patterns of extramarital sex (EMS) remains sparse. This study aimed to fill this gap, using data from a population-based, repeated cross-sectional survey administered at four time points during the period 2000-2015. EMS was assessed by asking whether a person in marriage had engaged in sexual activity with someone else during the relationship with his/her current partner. Our findings showed that among married adults aged 20-59, the occurrence rate of EMS nearly tripled over the period 2000-2015, increasing from 12.9% to 33.4% for men, and from 4.7% to 11.4% for women. Moreover, in the early years of this century, EMS was negatively associated with older age (50-59 years), lower educational level (elementary and below) and rural residence for men, and negatively associated with older age and positively associated with higher educational level (college and above) for women. All these differences, however, disappeared in more recent years. Overall, this study indicates a marked increase in EMS, a widening gender gap in EMS, and for each gender, a convergence of EMS across various sociodemographic groups.