In new guidelines, ACOG says IUDs and contraceptive implants should be considered "first-line" birth control options for teenagers. The group issued similar advice for adult women last year (see Reuters Health story of June 21, 2011).

IUDs, or intrauterine devices, are implanted in the uterus, where they release small amounts of either copper or the hormone progestin to prevent pregnancy. The contraceptive implant, about the size of a matchstick, is inserted under the skin of the arm, where it releases controlled amounts of progestin.

In the U.S., IUDs and implants are much less popular than birth control pills and condoms for contraception. Many experts would like to see that change, since IUDs and implants - known collectively as long-acting reversible contraceptives - are far more reliable.

"Nearly all women who are sexually active are good candidates for long-acting reversible contraception," said Dr. David L. Eisenberg, an assistant professor of obstetrics and gynecology at Washington University in St. Louis School of Medicine.

"It's exciting that ACOG is being so declarative that we should be treating adolescents the same as adults" when it comes to birth control options, said Eisenberg, who was not involved in writing the new statement.

IUDs and implants are so effective because they are "set and forget" contraceptives, and are not dependent on couples using them correctly.

That could make them especially good choices for teenagers, Eisenberg noted, since teens often use birth control inconsistently or not at all.

The hormonal IUD, sold under the brand name Mirena, can prevent pregnancy for five years, while the copper version, sold as ParaGard, is effective for about 10 years. The contraceptive implant (Implanon) works for three years.

Research shows that 0.8 percent of U.S. women using a copper IUD have an unplanned pregnancy within a year. The rate for those on the hormonal IUD was 0.2 percent.

Contraceptive implants, meanwhile, are even more effective - with a one-year pregnancy rate of just 0.05 percent.

In contrast, about nine out of every 100 women on birth control pills can expect to have an unintentional pregnancy in a year - owing largely to imperfect use. With condoms, about two percent of women will become pregnant, but that's only if a couple uses them correctly, every time they have sex.

SIDE EFFECTS, COSTS

Both IUDs and implants can have side effects, ACOG points out. With the implant, irregular menstrual bleeding is most common; some women stop having their periods altogether.

The Mirena IUD may also cause menstrual irregularities. But it generally makes periods lighter, which is why it is also approved as a treatment for heavy bleeding. The ParaGard IUD has the opposite effect: menstrual bleeding and cramping can increase, though that may go away over time.

In about one in 1,000 cases, ACOG says, the IUD can push through the wall of the uterus. It then needs to be removed, which sometimes requires surgery.

When they first came out, IUDs were considered an option mainly for women who'd already had children, as Reuters Health reported last year.

That was based on worries that IUDs raised the risk of pelvic inflammatory disease (PID), which can cause infertility. So doctors were reluctant to place IUDs in younger women who had not yet had a baby.

That "myth" might be one reason that health providers are even less likely to talk about IUDs and implants to teenagers than to adult women, according to Eisenberg.

But he said another barrier for teenagers is the type of health provider they typically see. Teens may see a family doctor or pediatrician - who may be less likely than an ob/gyn to be knowledgeable about IUDs and implants, or less comfortable placing them.

Cost could be another problem.

The upfront cost of the Mirena device itself is nearly $800. The ParaGard price tag is about $500. Then there are the doctor's charges for inserting them.

The Implanon implant costs between $400 and $800, with all charges considered.

Even if a teenager is covered by her parents' insurance, she might not want her parents finding out about her birth control payment. So, Eisenberg said, it may well seem easier to pay for condoms or birth control pills (generic pills run for about $10 a month.)

Healthcare providers, ACOG says, should do their best to make IUDs and implants available to young women who want them. The devices, the group writes in Obstetrics & Gynecology, "are the best reversible methods for preventing unintended pregnancy, rapid repeat pregnancy, and abortion in young women."

Eisenberg told Reuters Health that when providers don't know much about the contraceptives, they should refer their teen patients to someone who does.

"All adolescents should be educated on all their birth control options," he said.

SOURCE: bit.ly/QrtS1u Obstetrics & Gynecology, October 2012.

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