Do teenagers respond to HIV risk information? Evidence from a field experiment in Kenya

We use a randomized experiment to test whether and what information changes teenagers' sexual behavior in Kenya. Providing information on the relative risk of HIV infection by partner's age led to a 28 percent decrease in teen pregnancy, an objective proxy for the incidence of unprotected sex. Self-reported sexual behavior data suggests substitution away from older (riskier) partners and toward same-age partners. In contrast, the official abstinence-only HIV curriculum had no impact on teen pregnancy. These results suggest that teenagers are responsive to risk information, but their sexual behavior is more elastic on the intensive than on the extensive margin.