"There appears to be no evidence suggesting a causal role of alcohol use in determining the probability of having sex."
The consequences of risky sexual behavior fall heavily on teenagers and young adults. In 2002, the incidence rate for chlamydia was 297 per 100,000 population for persons of all ages, 1483 for teenagers, and 1610 for young adults. Similar age disparities are found for gonorrhea, with incidence rates per 100,000 population of 125, 476, and 593, respectively. Moreover, approximately half of all new human immunodeficiency virus (HIV) infections in the United States occur among people under age 25. Current teen rates of pregnancy and out-of-wedlock birth in the United States are high by historical standards and high relative to other developed countries.
Although alcohol use has traditionally been associated with risky sexual behavior, there is still a question as to whether excess alcohol consumption causes an increase of risky sexual behavior among young adults. In An Investigation of the Effects of Alcohol Consumption and Alcohol Policies on Youth Risky Sexual Behaviors (NBER Working Paper No. 11378), co-authors Sara Markowitz, Robert Kaestner, and Michael Grossman ask whether alcohol use promotes risky sexual behavior and whether there are public policies that can reduce risky sexual behavior by reducing alcohol use.
The authors look at the influence of alcohol consumption on individual behavior using data from the National Longitudinal Survey of Youth and the biennial Youth Risk Behavior Surveys. Alcohol use was defined as the number of days in the past 30 days that an individual reported having had at least one drink of alcohol and the number of days on which five or more drinks were consumed. They conclude that, "there appears to be no evidence suggesting a causal role of alcohol use in determining the probability of having sex." There was some evidence, however, suggesting that alcohol consumption does "lower the probabilities of using birth control and condoms" among sexually active teens.
The authors use aggregate data on the reported incidence of gonorrhea and AIDS infections by state to measure whether state and federal taxes on beer, county laws banning alcohol sales, laws governing blood alcohol levels, and zero tolerance laws for underage drinking and driving affect infection rates. Though women appear unaffected, zero tolerance laws appear to decrease the gonorrhea rate in males aged 15-19, and a one percent increase in beer taxes is associated a 1.1 percent reduction in the gonorrhea rate in young men aged 15-19 and 20-24. Neither the percentage of the population living in dry counties nor laws controlling blood alcohol rates affected either rate of infection.
-- Linda Gorman