Continuity and change in premarital sex in Vietnam.

CONTEXT Premarital sexual activity is thought to be rising in Vietnam. However, there is little evidence documenting such an increase, and it is unknown whether levels of premarital sex differ between northern and southern Vietnam and whether premarital sex occurs primarily with a future spouse. METHODS Surveys conducted in northern Vietnam (Red River Delta) and southern Vietnam (Ho Chi Minh City and surrounding environs) in 2003-2004 among individuals married during one of three important periods in Vietnamese history (1963-1971, 1977-1985 or 1992-2000) were used to assess trends and regional differences in the prevalence and context of premarital sex. RESULTS In both regional samples, 31% of men who married in 1992-2000 reported having had premarital sex. The proportion was much lower among women (8% in the South, 12% in the North). The prevalence of premarital sex rose markedly across cohorts in the North but only modestly in the South. Relatively few men had premarital sex with someone other than a future spouse (3-23%). The proportion of the rise in the prevalence of premarital sex that was due to sex exclusively with a future spouse was greater in the North (42%) than in the South (25%). CONCLUSIONS These results suggest that premarital sex is becoming more common in Vietnam but is still not widespread. Better information about the sexual networks of men in the general population and their contacts with high-risk groups (e.g., commercial sex workers) is needed to ascertain the likelihood that HIV/AIDS will spread to the general population.