February 23, 2012 — Summary of "Associations Between Sexuality Education in Schools and Adolescent Births," Cavazos-Rehg et al., Archives of Pediatric and Adolescent Medicine, Feb. 14, 2012.
For this study, a team of researchers led by Patricia Cavazos-Rehg of the Department of Psychiatry at Washington University of St. Louis examined the effects of sex education practices on adolescent birth rates, while controlling for demographic, religious and political factors at the state level.
The researchers noted that on the whole, teen birth rates in the U.S. have been on the decline since the 1960s, although there was a slight uptick in 2006 and 2007 before the rates began to decline again. Despite the overall downward trend, U.S. teen birth rates remain disproportionately high compared with other developed countries. Thorough examination of school-based sex education programs is essential to better understanding the programs' impact on teens' sexual behaviors, the researchers wrote.
Because the reasons for the uptick in teen birth rates in 2006 and 2007 are unknown, the researchers focused on teen birth rate data from 1997 through 2005, using CDC statistics on girls ages 15 through 17. To determine the proportion of schools within a state that offered sex education, the researchers used information from CDC's School Health Profiles survey, which has periodically tracked practices in public secondary schools since 1995. They narrowed the data to 24 states that participated in the survey and had weighted data for at least three of the five years (1996, 1998, 2000, 2002 and 2004) that CDC had compiled the report. The researchers also determined a total measure of sex education instruction by creating an average score across 13 sex education topics.
The researchers compared the relationship between teen birth rates and the average score for all sex education topics, as well as with each specific topic. They included the year in their analysis "to account for trends in adolescent birth rates that could not be explained by any of our measured variables over time." The researchers then adjusted for states' demographic characteristics and religious/political climate.
From 1996 through 2004, a "relatively high" percentage of schools in the 24 states taught sex education topics, although the percentage that included instruction on how to use a condom was much lower, the researchers found. Alaska had the lowest average score of sex education topics taught (68.8%) and New York had the highest (91%).
The higher a state's religiosity, the less condom education was taught. Political ideology also was associated with most of the sex education topics, "indicating that the more liberal the state, the more sexuality education topics were taught," the researchers found.
The average birth rate for girls ages 15 through 17 was 25.6 births per 1,000 girls, which gradually declined to 17.7 births per 1,000 girls in 2005. New Hampshire had the lowest average birth rate during the study period (9.7 per 1,000) and Arkansas had the highest (34.8 per 1,000).
Within states, changes in teen birth rates over time were not associated with changes in most of the sex education topics. When the researchers compared data between states, they found that states with higher average percentages of schools teaching sex education topics tended to have lower teen birth rates. A 1% increase in a state's average score across all sex education topics taught was associated with 0.6 fewer births per 1,000 girls ages 15 through 17, they found.
There was a significant association between teen birth rates and eight of the 13 sex education topics: HIV prevention, pregnancy prevention, sexually transmitted infection prevention, abstinence as the most effective method to avoid HIV infection, how HIV is transmitted, condom, efficacy, how to use a condom and human sexuality. However, for many of the topics, the association with teen birth rates lost significance after adjusting for the time trend and demographic characteristics, the researchers wrote.
Within states, the higher the proportion of whites, the lower the birth rates were. Between states, both a higher average poverty level and higher level of religiosity were associated with a higher teen birth rate. States without laws requiring parental involvement in minors' abortions tended to have lower teen birth rates, compared with states with such laws.
Higher teen birth rates were associated with poverty and with minority status, as well as more conservative state characteristics, including higher religiosity and stricter abortion laws, the researchers wrote.
The "main findings revealed that sexuality education was not associated with teen birth rates once religiosity measures and abortion policy were included in the analysis," they added. Therefore, the provision of sex education did "not independently explain the considerable variations in adolescent birth rates found across theses states," according to the researchers.
Separating the effects of state characteristics from the effects of sex education on teen birth rates is "complex," but there are several possible explanations for the higher teen birth rates in more conservative states, the researchers continued. One possible explanation is that more conservative and religious states do not fully implement sex education programs; it also is possible that teens in those states tend to disregard the educational messages. Another possibility is that female adolescents in states with more conservative values, higher religiosity and stricter abortion laws are less likely to have an abortion, compared with their peers in other states.
The researchers urged policymakers in conservative states with high teen birth rates to "pragmatically identify methods to reduce the rate," including by embracing comprehensive sex education. "Policymakers, health care providers, researchers and other key stakeholders must realistically address these confounding issues when evaluating and implementing sexuality education programs," with the teen birth rate as their metric of success or failure, the researchers wrote.