Final answer:
The rate of premarital sex among U.S. adolescents between 1991 and 2013 has decreased, indicating that changes in sexual attitudes and the acceptance of non-traditional family structures do not necessarily lead to higher rates of adolescent premarital sex.
Step-by-step explanation:
Between 1991 and 2013, the overall rate of premarital sex among U.S. adolescents decreased. While there might be perceptions that premarital sex rates are increasing, especially with societal changes and a shift in sexual attitudes, evidence such as the National Survey of Family Growth and other studies indicate a decline in adolescent premarital sex. Societal attitudes have become more accepting of certain behaviors, such as the belief that it's acceptable for an unmarried female to have a child, but these attitudes do not necessarily translate to increased levels of premarital sex.
Further analysis of sexual attitudes in the United States shows that despite a more restrictive societal view on sex compared to other industrialized nations, the youth still hold traditional values, like monogamy, in high regard. Education and societal norms influence perspectives, but they don't always correlate with an increase in premarital sexual activities.