美国妇产科医师学会(ACOG)在10月刊《妇产科学》杂志(Obstetrics & Gynecology)上发表声明指出，医生应鼓励性活跃的青少年考虑选用长效可逆避孕(LARC)方法(2012;120:983-8)。


ACOG意见书中指出，15~19岁青少年中42%有性行为，82%的青少年妊娠为意外妊娠。意见书建议使用长效醋酸甲羟孕酮(DMPA)注射剂、避孕贴剂、阴道环、口服避孕药、避孕套和其他短效方法作为青少年的主要避孕措施。但意见书同时指出，与LARC方法相比，这些方法在青少年中的持续使用率较低，而且与较高的妊娠发生率相关。例如，一项2011年发表的研究显示，在实施短效避孕的15~24岁女性中，避孕贴剂在1年时的持续使用率仅为11%，DMPA为16%，口服避孕药和阴道环为30%。而另一项研究显示，在20岁以下女性中，左炔诺孕酮宫内节育系统和避孕埋植剂在1年时的持续使用率为85%，含铜宫内避孕器(IUD)1年时的持续使用率为72%。


在美国，LARC方法的使用率已从2002年的2.4%增至2009年的8.5%。但在青少年中，LARC(主要为IUD)的使用率仅为4.5%。在所有年龄组中，2006年获批上市的单杆激素避孕药依托孕烯埋植剂的使用率非常低：在美国采取避孕措施的女性中，使用率不足1%，在15~19岁女性中，使用率为0.5%。


意见书指出，妨碍青少年使用LARC的因素包括费用、缺乏渠道和医生对安全性担心等。通过加强对医生的培训和教育，可以消除一些障碍。在正确使用的情况下，LARC的妊娠率低于1%，是预防青少年意外妊娠、快速反复妊娠和堕胎的最佳可逆方法。IUD和避孕埋植剂等LARC方法的并发症较为罕见，并且在青少年中观察到的并发症与在较年长女性中观察到的相似。鉴于LARC方法的有效性高、满意率和持续使用率也较高，同时不需每日用药，因此建议将其作为所有女性和青少年的一线避孕方法，同时建议联合持续使用避孕套，以降低性传播感染的风险。意见书建议青少年应在植入IUD前或植入IUD的同时常规筛查性传播感染。


相关评论：证据支持在青少年中使用LARC


新墨西哥大学的Rameet H. Singh博士表示，避孕药和避孕套是美国青少年最常使用的避孕措施，但与LARC方法相比，失败率高且停用率高。纳入超过9,000例14~45岁女性的CHOICE前瞻性队列避孕研究显示，在消除费用等影响使用的障碍并给予适当指导后，超过40%的14~17岁女性选择埋植剂，超过40%的18~20岁女性选择IUD。另一项研究显示，在到节育门诊就诊的青少年中，有超过一半未曾听说过宫内避孕，但在医生给予适当介绍指导后，这些青少年对使用宫内避孕的兴趣提高了2倍。LARC方法兼具避孕和避孕之外的益处，并且很少有绝对禁忌证。推广LARC的使用将可减少美国青少年人群的意外妊娠。


ACOG的1名委员会成员是依托孕烯埋植剂Nexplanon的培训师。Singh博士声明无相关经济利益冲突。

 

Health care professionals should encourage sexually active adolescents to consider long-acting reversible contraceptive methods when counseling them about contraceptive choices, according to an American College of Obstetricians and Gynecologists’ committee opinion.


 

With pregnancy rates less than 1% with perfect and typical use, long-acting reversible contraception (LARC) methods "are the best reversible methods for preventing unintended pregnancy, rapid repeat pregnancy, and abortion in young women," the opinion states. Although the complications of these methods – intrauterine devices and the contraceptive implant – are rare and are similar in adolescents and older women, they are underused in the younger age group, according to ACOG committee opinion No. 539, written by the Committee on Adolescent Health Care’s Long-Acting Reversible Contraception Working Group. The opinion was published in the October issue of Obstetrics & Gynecology (2012;120:983-8).


 

"Increasing adolescent access to LARC is a clinical and public health opportunity for obstetrician-gynecologists," the opinion says, adding: "With top-tier effectiveness, high rates of satisfaction and continuation, and no need for daily adherence, LARC methods should be first-line recommendations for all women and adolescents," combined with the use of consistent use of condoms to reduce the risk of sexually transmitted infections.
 
The new opinion is a reaffirmation of the committee opinion issued in 2007. "We’ve had the support to offer these top-tier methods as first line for adolescents for years ... and yet teens are largely using condoms, oral contraceptive pills, and withdrawal – methods with much, much higher failure rates – for contraception, if they are using anything at all," said Dr. Melissa Kottke, a member of the committee and medical director of the Jane Fonda Center for Adolescent Reproductive Health at Emory University in Atlanta.


 

Health care providers are not routinely offering these methods to teens, possibly because they mistakenly think that teens will not choose these methods, which data indicate is not the case; and they may not have the training or comfort level to provide them, she said in an interview. Clinicians may also believe that LARCs are only appropriate for parous teens and there is a "lingering fear of infection," but there are data that support the safe use of IUDs and the implant in both parous and nulligravid teens, she said, adding that all women, including adolescents, should be counseled on condom use and other approaches to decrease their risk of sexually transmitted infections.


 

The opinion recommends that adolescents should be routinely screened for sexually transmitted infections when or before an IUD is inserted.


 

Among the statistics cited in the ACOG opinion is that 42% of all adolescents aged 15-19 years have had intercourse and 82% of adolescent pregnancies are not planned.


 

The opinion refers to depot medroxyprogesterone acetate (DMPA) injection, the contraceptive patch, vaginal ring, and OCs, as well as condoms and other short-acting methods, as adolescent contraceptive "mainstays," but points out that these methods are associated with lower continuation rates and higher pregnancy rates among adolescents than LARC methods. For example, a study published in 2011 found that 1 year after starting a short-acting contraceptive, continuation rates among women 15-24 were as low as 11% for the contraceptive patch, 16% for DMPA, and about 30% for OCs and the vaginal ring. But in another study, continuation rates for the levonorgestrel intrauterine system and contraceptive implant among women under aged 20 at 1 year were 85%, and copper IUD continuation rates at 1 year among adolescents were 72%.


 

The use of LARC methods have increased in the United States, from 22.4% in 2002 and 8.5% in 2009. But among teenagers, about 4.5% of adolescents use LARC, mostly IUDs. Use of the contraceptive implant, the etonogestrel single-rod contraceptive approved in 2006, is low in all age groups (less than 1% of the women in the United States using contraception and 0.5% of those aged 15-19 years), according to the opinion.


 

The committee cites barriers to use of LARCs by adolescents – including cost, lack of access, and concerns among health care providers about their safety in younger patients – and note that training and education programs "should address common misconceptions and review the key evidence and benefits of adolescent LARC use."


 

In the interview, Dr. Kottke, also with the department of gynecology and obstetrics at Emory, said that she believed that many of these barriers "can be overcome with clinician support, education and training ... and the impact on the health and wellness of our adolescent patients and our communities will be substantial."


 

She disclosed that she has been an Implanon trainer in the past. (Nexplanon, the etonogestrel implant, is the only contraceptive implant currently on the market; it is a radiopaque version of Implanon, which is no longer available.)


 

This opinion replaces ACOG committee opinion No. 392, published in December 2007.


 

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Evidence Supports LARC Use in Teens


 

This committee opinion is an excellent resource for clinicians taking care of adolescents. It succinctly and comprehensively provides the evidence to show that long acting reversible contraceptives (IUD and implant) should be offered as first line methods to adolescents.


 

In 2008, twice as many teenagers in the United States became pregnant, compared with Sweden. Birth control pills and condoms are the most popular forms of contraceptives used by teens in the United States, and have higher failure rates compared with LARC methods and high discontinuation rates. While the uptake of LARC nationally has been low in the adolescent population, data from the contraceptive CHOICE study found that with appropriate counseling, and no financial, logistical, provider or other barriers to use, over 40% of females aged 14-17 years chose the implant and over 40% of those aged 18-20 years chose an IUD. The study is a prospective cohort of more than 9,000 women aged 14-45 years who desired contraception, and after enrolling in the study were given comprehensive contraceptive counseling and their choice of contraception free of cost for a specified duration, after enrollment.


 

Another study of teens attending a family planning clinic showed that more than half had not heard of intrauterine contraceptives and when counseled appropriately by health care providers, they were three times more likely to be interested in using it.


 

LARC methods have both contraceptive and noncontraceptive benefits. There are few absolute contraindications to using LARC methods, and increasing their use has the potential to reduce unintended pregnancy in the U.S. adolescent population with appropriate counseling and in the absence of financial, logistical, provider or other barriers.