More than half of teenagers who sign public pledges to remain abstinent until marriage have sex within one year of making the pledge, according to a report released this week by Harvard University, the Los Angeles Times reports (Mehren, Los Angeles Times, 5/8). Janet Rosenbaum, who conducted the study -- which was published in the June issue of the American Journal of Public Health -- examined data from the government-sponsored survey, National Longitudinal Study of Adolescent Health, which was conducted by the National Institute of Child Health and Development (Nagourney, New York Times, 5/9). The survey interviewed 14,000 U.S. adolescents ages 12 to 18 in 1995 and again in 1996 and 2001. According to study findings, 52% of participating teens who made the pledge in 1995 reported having intercourse within one year. In addition, 73% of the respondents who in the first survey said they had signed a pledge but later had sexual intercourse denied making the pledge when they were surveyed again. Nearly one-third of participating adolescents who in the first survey said they had had intercourse reported in the second survey that they had never had intercourse (Los Angeles Times, 5/8). The study says, "Survey respondents typically reconcile their memories with their present beliefs. ... Respondents may recall only memories consistent with their current beliefs or report actions that did not occur but are consistent with their current beliefs" (New York Times, 5/9). Rosenbaum said that adolescents who sign virginity pledges "are more likely to give bad information ... about their sexual history" (Los Angeles Times, 5/8). According to the New York Times, the study does not only discuss the "reliability of the [virginity] pledges and abstinence programs, [but also] raises concerns about whether" these programs make tracking STIs more difficult (New York Times, 5/9).