These findings lead some researchers to believe that spending hundreds of millions in federal dollars to teach young adults about waiting until marriage to become sexually active is waste. But some aren't so sure.
Study author Lawrence Finer said, "This is reality-check research. Premarital sex is normal behavior for the vast majority of Americans, and has been for decades."
The study, done by Guttmacher Institute -- a New York think tank that studies sexual and reproductive issues -- was published in the current issue of Public Health Reports.
The study surveyed 38,000 people from the early 1980s to 2002 and included findings from the federal National Survey of Family Growth and found that 99 percent had sex before age 44 and 95 percent of them had done so before marriage.
The study also found that men and women as far back as the 1940 were having premartial sex.
While Guttmacher Institute found the findings to be fuel to their debate against the federally-funded programs, one official said that even if the programs don't stop teens from having premarital sex it might delay it.
Wade Horn, assistant secretary for children and families at the U.S. Department of Health and Human Services, said, "One of its values is to help young people delay the onset of sexual activity. The longer one delays, the fewer lifetime sex partners they have, and the less the risk of contracting sexually transmitted disease."
