Teenagers can tend to live dangerously and society today gives them plenty of opportunities to do so. As a result, we are seeing epidemics of youthful drunkenness, drug-induced mental illness and sexually transmitted diseases, to mention only three of the excesses young people seem prone to. This week in Britain there are calls for the legal drinking age to be raised to 21 following the murder of a 47-year-old father of three by a gang of drunken youths. The government is redoubling efforts to educate young people about the harm of alcohol. Since the younger that one starts on substance abuse the more harm it can do, the best choice for young adolescents is, clearly, no alcohol -- and no smoking or other drugs either.

But what about no sex? Is this the best choice for teenagers and should we be doing our utmost to persuade them to abstain from sexual experimentation? Or is abstinence an unattainable goal for the majority of young people -- based on ideals about love and sex that are merely a hangover from the past? Have we done our best when we mention that it is "OK not to have sex" and then spend the rest of the time telling kids how to "protect" themselves if they do? These questions indicate two approaches to educating youngsters about sex which currently seem to be in head-on conflict, especially in the United States where the future of government funding for "abstinence only" programs hangs in the balance.

Are we ready to convey what is best for our children and rely on their
capacity for making right decisions? Or, should we pessimistically and
patronisingly decide for them that they cannot achieve risk avoidance
and that they have no other choice than to reduce risks?

In the resulting, highly politicised environment research findings can be critical. Two recently published reviews of abstinence only curricula in the US have given rise to a crop of headlines announcing that "abstinence education doesn't work". The latest is a review(1) in the influential British Medical Journal of 13 scientific trials of abstinence programs by a group of researchers at Oxford University, who came to the conclusion that such programs are "ineffective".

Abstinence educators should not be too readily discouraged by such findings. Kristen Underhill and colleagues searched for trials that aimed to prevent HIV infection -- the bottom line in sex education -- and were more or less well designed. But the studies they found are a very mixed bag, and although the researchers have done a great job of summarising this material, their findings gloss over very serious methodological problems. For example, how does one compare programs that ranged in duration from one session to 720 sessions, or evaluate outcomes reliably when there are dropout rates from 5 per cent to 45 per cent? Given these problems, the total number of young people in the studies -- 15,940 -- has no special relevance, even though it is cited as though it gives extra authority to the review.

Despite such shortcomings, the authors bluntly state that, "evidence from this review suggests that abstinence only programs that aim to prevent HIV infection are ineffective". This is corroborated by a friendly editorial(2) in the BMJ which speaks of the studies being "remarkably consistent" in suggesting that abstinence only programs increased neither primary nor secondary abstinence. The editorialists go further, claiming that, "In contrast to abstinence only programs, programs that promote the use of condoms greatly reduce the risk of acquiring HIV." They cite in support three papers, two of which are from the late 1990s. The editorial finally argues that money should not be spent on abstinence only programs but rather on condom promotion programs.

I am not sure under what criteria other studies showing the contrary are excluded before such statements are made. For example, a trial in Uganda found an increase in HIV risky behaviours in the intervention group where condom use and supply was promoted.(3) And a meta-analysis by Dicenso and colleagues(4) showed various programs, including ones in family planning clinics, were actually not very effective at improving contraceptive use, delaying sexual debut or avoiding unwanted pregnancies. No-one then requested the elimination of funding to family planning clinics.

In the light of the problems encountered by the Oxford team it might have been safer to say there is no evidence that the 13 particular abstinence only programs they reviewed have done any better than the alternatives evaluated. This does not mean "abstinence promotion does not work", which is what some -- including the Spanish paper El País a couple of weeks ago -- are trying to convey to the public.

In any case, whether those programs worked is not the real issue. The real issue is whether we are asking ourselves the right questions about them. Do we really expect that "abstinence promotion" during a few school sessions will work in a society where the media are conveying exactly the opposite message? (5)

Think of gender violence, sexism, discrimination, academic failure, lack of exercise, unhealthy eating, the problem of drinking and driving, smoking and other drug taking. Would a dozen classes in eighth or ninth grade change these behaviours if everywhere else the message was different?

The question for these issues is "how" can we convey the right message and not "whether" we should convey them. If a program aiming to prevent gender violence does not succeed, it would be a terrible mistake to conclude that "education against violence is not effective". We would rather have to think of a way to do it better given that this particular program had failed, or we would have to think of how we could help this program to succeed.

Let us not forget many anti-smoking programs have little success and no one doubts we should prevent smoking in youth. Do we really expect that "abstinence promotion" during a few school sessions will work in a society where the media are conveying exactly the opposite message? The question is: do we really believe abstinence is a good choice for our youth and do we really want to promote abstinence?

I am not necessarily a defender of "abstinence only" programs, at least not for older adolescents. I personally believe the whole truth is the best we can give to our youth in order to help them make better and healthier choices. But we should empower youth to be able to make the best choices and, when behaviours are involved, this includes character education. We cannot just give them information and slogans; we have to help young people internalise good values and develop the skills, or habits, that go with them. This is not the work of one program.

It is always best to "avoid risks" rather than to "reduce risks" and messages should be tailored to specific target groups. There is sound epidemiological evidence in favour of the ABC strategy of prevention -- Abstain, Be faithful, or use Condoms. Abstinence and being mutually faithful are best for avoiding risk whereas condoms reduce risk in people who choose not to avoid risks with "A" nor "B".

A consensus statement published by The Lancet in 2004 (6) emphasised the importance of prioritising messages by calling for a delay of sexual debut in youth or for the return to abstinence in those who are having casual sex. When having sex is chosen, the consensus prioritised the message of mutual monogamy. Those who choose not to accept "A" nor "B", should be advised they can reduce, albeit never totally eliminate, the risk of infection.

The Lancet consensus signers did not believe it is sound public health policy to give the exact same priority to one message (condom use) to teens who have not began to be sexually active and to persons working in commercial sex. All the truth should be conveyed but "abstinence plus" programs have to be "abstinence centred" and not just programs that add condom information to abstinence promotion at the same level. There is evidence showing that abstinence-centred programs are helpful.(7)

On the other hand, condom promotion (risk reduction) may, if not carefully
implemented, actually foster a false sense of security in youth and lead,
paradoxically, to increased risk taking behavior and vulnerability such as
beginning sex at earlier ages and having more sex partners. This is known as "risk compensation".(8, 9) No African country has succeeded in reducing HIV incidence with programs which relied exclusively on condom promotion, whereas the countries which have reduced HIV incidence have integrated "A" and "B" in comprehensive national programs.(10)

Our major problem is to decide what we want to convey to our youth. It is unlikely any program will help change risky behaviour unless youth are given truthful information, and unless they are empowered with life skills as they are through character education. This can hardly be achieved unless society at large and especially educational and health authorities make the right effort to convey consistent messages to specific target groups, thus helping parents do their job at home as well.

Are we ready to convey what is best for our children and rely on their capacity for making right decisions? Or, should we pessimistically and patronisingly decide for them that they cannot achieve risk avoidance and that they have no other choice than to reduce risks?

Jokin de Irala, MD, is Deputy Director of the Department of Preventive Medicine and Public Health in the Faculty of Medicine at the University of Navarre, Spain. He holds a Master of Public Health degree from the University of Dundee, Scotland and doctorates in medicine (University of Navarre, Spain) and biostatistics and epidemiology (University of Massachusetts). In November he will be speaking at the Second International Congress on Education in Love, Sex and Life, in Manila.)

1. Underhill K, Montgomery P, Operando D. Sexual abstinence only programs to prevent HIV infection in high income countries: systematic review. BMJ2007;335:248-

2. Hawes S, Sow PS, Kiviat NB. Is there a role for abstinence only programs for HIV prevention in high income countries? BMJ 2007;335:217-218

3. Kajubi P, Kamya MR, Kamya S, Chen S, McFarland W, Hearst N. Increasing condom use without reducing HIV risk: results of a controlled community trial in Uganda. J Acquir Immune Defic Syndr 2005; 40: 77-82.

4. DiCenso A, Guyatt G, Willan A, GriffithL. Interventions to reduce unintended pregnancies among adolescents: systematic review of randomised controlled trials. BMJ 2002;324:1426-1435

5. Collins RL, Elliott MN, Berry SH, Kanouse DE, Kunkel D, Hunter SB, Miu A. Watching sex on television predicts adolescent initiation of sexual behavior. Pediatrics 2004;114:280

6. Haleprin D, Steiner M, Cassel M, Green E, Hearts N, Kirby D, et al. The time has come for common ground on preventing sexual transmission of HIV. Lancet 2004; 364: 1913-1915.

7. Cabezon C, Vigil P, Rojas I, Leiva ME, Riquelme R, Aranda W, Garcia C. Adolescent pregnancy prevention: An abstinence-centered randomized controlled intervention in a Chilean public high school. J Adolesc Health. 2005;36:64-

8. De Irala J, Alonso A. Changes in sexual behaviours to prevent HIV. Lancet. 2006;368:1749-50.

9. Cassell MM, Halperin DT, Shelton JD, Stanton D. Risk compensation: the Achilles' heel of innovations in HIV prevention? BMJ 2006; 332: 605-7.

10. Stoneburner RL, Green T, Hearst N, McIlhaney J. Evidence that Demands Action; Comparing Risk Avoidance and Risk Reduction Strategies for HIV Prevention. In: Edited by Patricia Thickstun KH, editor: The Medical Institute, 2004.

This article has been adapted by Jokin de Irala and Carolyn Moynihan from a letter published in the British Medical Journal online.