When teenage girls have babies, they are in danger. They more likely will suffer serious health problems than mothers in other age groups and more often will drop out of school and become stuck at low-income levels for life. Children of these teens also navigate a tough road. They are prone to health and behavior trouble, tend not to do well in school and frequently become teen parents themselves.

Unfortunately, the U.S. has a lot of teen parents—273,000 births in 2013, which works out to a greater rate for the nation's population than for other developed countries, such as the U.K. and Canada. Abortion rates are also high. Longer-lasting birth-control methods can change this situation, and research now points to cost-effective ways to do so.

Whereas condoms are best for preventing sexually transmitted diseases, they are often not used, resulting in unwanted pregnancies. Girls need other choices. The evidence favoring long-acting implants such as intrauterine devices (IUDs) is so powerful that in September 2014 the American Academy of Pediatrics endorsed IUDs as the best contraception option for teens, and the American College of Obstetricians and Gynecologists has done the same. Here are some of the reasons: a study of more than 1,400 young women in the St. Louis area published last year in the New England Journal of Medicine found that providing teen girls with IUDs and other hormonal implants reduced pregnancy and abortion rates by more than 75 percent over three years. A 2012 study concluded that women using IUDs were 17 times less likely to get pregnant unintentionally than were women using pills, patches or vaginal rings.

But insurance companies often do not pay for IUDs or other long-duration devices, and an implant without insurance is 50 to 100 times the price of a condom package. Because of these costs and other access barriers, only 5 percent of American adolescents use effective, long-acting methods. When obstaclesare removed, the numbers change dramatically. Seventy-two percent of the teens in the New England Journal of Medicine study chose IUDs or other implants when given that option.

Implants are not for everyone, but teens who use contraception and their parents, who are guiding these important life decisions, should be able to make the healthiest choices. That is, in fact, the law of the land. The federal Affordable Care Act requires that employer-provided insurance cover, without co-payments, all forms of birth control approved by the U.S. Food and Drug Administration. There are, however, current court cases challenging the act's contraception provision, and many insurers flout the rule.

One state, Colorado, offers a good model for how to give the most effective birth control to at-risk teens, avoid the legal murk and save taxpayer money at the same time. It has had stunning success with a pilot program to distribute more than 30,000 contraceptive devices to low-income women through 68 family-planning clinics. By using clinics that did not charge for devices, Colorado sidestepped insurance coverage costs and made Affordable Care Act challenges irrelevant. The program also made a big difference to teens. It started in 2009. During the next four years, the teen birth rate plunged by 40 percent; between 2009 and 2012 the teen abortion rate fell by 35 percent. The initiative saved taxpayer money, too, according to the state. The multiyear program cost $27.3 million overall, but in just one year it saved Colorado $42.5 million in health care expenses.

Programs such as Colorado's should be expanded—yet eventhat one is threatened. The initiative was funded by a private donor, but money is running out, and the state's general assembly has voted against additional funding. The federal government can step in to fill the gap, there and in other states. It should finance the distribution of long-acting contraceptives at clinics that can reach teens directly. As in Colorado, these programs will ultimately save taxpayer dollars. Most important, such efforts will reduce rates of teen pregnancy, birth and abortion, along with their unhappy consequences for us all.