Teens who were educated about methods of birth control and who received free contraception were significantly less likely to get pregnant or to get an abortion compared to other sexually active teens, according to a study published in the New England Journal of Medicine.

Nearly three-quarters of the 1,404 teens who took part in the Contraceptive CHOICE Project chose intrauterine devices, or IUDs, which are small devices placed in the uterus to interrupt the process of insemination, or contraceptive implants, which are small plastic rods inserted into the arm that continuously release a synthetic hormone called progestin to prevent pregnancy. Health workers in the project promoted these forms of contraception since they are long-acting, providing protection for up to 10 years.

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In the larger population, just 5 percent of U.S. teens choose these forms of long-acting birth control. Most teens try shorter-acting forms of contraception, such as birth control pills or condoms, or use no contraception at all, due to factors such as cost and lack of access.

The teens in the study who chose IUDs or implants also used them for longer than those who chose short-acting forms of contraception such as the pill. After two years, two-thirds of the teens in the study who had chosen long-acting birth control were still using the IUDs or implants. Only one-third of teens who had chosen short-acting birth control were still using it after two years.

The Contraceptive CHOICE Project included more than 9,000 St. Louis women and teens who were at high risk for unplanned pregnancy and were open to trying a new form of birth control. Participants had various birth control options to choose from, including IUDs, implants, pills, rings, condoms, and patches. 

Of the teens in the study, nearly 500 were between 14 and 17 years old when they enrolled. Half of the teens in this age group reported that they had had an unplanned pregnancy, and 18 percent reported at least one abortion.

“The CHOICE Project removed three important barriers for teens … education, access, and cost,” said Gina Secura, Ph.D., a researcher at the Washington University School of Medicine in St. Louis and director of the CHOICE Project, in a press statement. “The simultaneous removal of these common barriers ... resulted in much lower pregnancy rates. By simply removing one barrier, we probably would not have seen the same results.”

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The results of the birth control intervention were astounding. The annual pregnancy rate for teens ages 15 to 19 in the study was 3.4 percent. That compares to 15.9 percent for all U.S. teens who are sexually active. Teens in the study had an average annual birth rate of 1.9 percent, compared to 9.4 percent for all sexually active U.S. teens.

Teens in the study also had lower abortion rates. From 2008 to 2013, the average annual abortion rate for teens in the study was almost 1 percent. That compares to 4.2 percent in 2008 for all sexually active teens.

“The study suggests that we can successfully reduce these outcomes [teen pregnancies, births, and abortion rates] if we make changes in how we provide contraceptive care to teens in the U.S.,” Secura said.

The U.S. Centers for Disease Control and Prevention aims to reduce the nation's teen birth rate by 20 percent by 2015.

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