Experts say abstinence-only sex ed can be harmful for many teens.

A recent report concluded that sex education that promotes waiting to have sex until marriage can be harmful, misguided, and stigmatizing for many teens.

The report published in the Journal of Adolescent Health found that these abstinence-only-until-marriage programs (AOUMs) made little difference in teen sexual behavior, and could even be harmful or shaming for some teens — and even affect their mental health.

Researchers from the Columbia University Mailman School of Public Health, University of North Carolina at Chapel Hill, University of Massachusetts Amherst, and other institutions, reviewed data from past published studies to see whether AOUM programs appeared to affect teen sexual behaviors.

The programs advocate abstaining from sex until marriage, and advise that abstinence is “the only certain way to avoid out-of-wedlock pregnancy, sexually transmitted diseases, and other associated health problems.”

An estimated $2 billion in federal funds have been spent on these programs since 1982, despite little evidence of their effectiveness. Additionally, comprehensive sex education, which includes information about condoms and contraception, has been decreasing since the mid 1990s, according to the report.

The researchers also found that AOUM programs were ineffective at reducing rates of HIV infection, and that teens included in these programs did not change their sexual behaviors — such as delaying having sex for the first time — compared with those in control groups that had not received sex education.

Teens who had comprehensive sex education that focused on risk reduction had a smaller chance of becoming pregnant or infected with HIV or another sexually transmitted disease (STD), according to their research.

The researchers also pointed out that these programs can be misleading, and essentially are not based on realistic teen behaviors.

The average time span between the first time a person has sex and the time when they get married has risen to approximately 8.7 years for young women and 11.7 years for young men, according to the report.

Additionally, while the programs tout that abstinence is the “only” way to ensure girls do not become pregnant or get STDs, the researchers found that message misleading.

“The weight of scientific evidence shows these programs do not help young people delay initiation of sexual intercourse. While abstinence is theoretically effective, in actual practice, intentions to abstain from sexual activity often fail,” co-author Dr. John Santelli, MPH, professor of Population and Family Health and Pediatrics, said in a statement.

“These programs simply do not prepare young people to avoid unwanted pregnancies or sexually transmitted diseases,” Santelli wrote.

Despite increased evidence that these programs don’t work as well as comprehensive sex education, the authors found that programs with comprehensive sex education have been decreasing in the U.S. over the last 20 years.

Researchers found that in 1995, 81 percent of adolescent boys and 87 percent of adolescent girls “reported receiving formal instruction about birth control methods.” However, nearly two decades later this number had fallen to 55 percent of boys and 60 percent of girls.

AOUM programs often ignore sexual health information that would pertain to members of the LGBTQ community, according to the researchers. Not only can that lead to sexual health consequences, but it can affect the mental health of teens who are LGBTQ.

“These programs are largely heteronormative and often stigmatize other sexualities as deviant,” the authors wrote. “Stigma and discrimination can contribute to health problems such as suicide, feelings of isolation and loneliness, risk for HIV infection, substance abuse, and violence among sexual minority youth.”

In addition, these programs focus on traditional gender roles, such as female passivity and male aggressiveness, which have been associated with risky sexual behaviors.

“Rigid gender beliefs and gender power imbalance are associated with risky sexual health behaviors including reduced likelihood of condom and contraceptive use,” the authors explained.

Megan Donovan, JD, Senior Policy Manager at the Guttmacher Institute, said these programs can lead teens to feel badly about themselves or their actions if they don’t adhere to the rigorous framework of AOUM programs.

“This reaffirms yet again that this type of approach — abstinence only… [is] ineffective and ultimately can have harmful and stigmatizing impacts on young people,” she told Healthline.

Donovan’s colleague from the Guttmacher Institute was a co-author on the paper, but Donovan was not involved in its publication.

Leslie Kantor, PhD, MPH, assistant professor of Population and Family Health at the Mailman School of Public Health and vice president of Education at Planned Parenthood Federation of America, said it’s key to give young people information about healthy and effective safe sex practices.

“Young people have a right to sex education that gives them the information and skills they need to stay safe and healthy,” Kantor said in a statement. “Abstinence-only-until-marriage programs leave all young people unprepared and are particularly harmful to young people who are sexually active, who are LGBTQ, or have experienced sexual abuse.”