Encouraging young people to delay having sex is an essential element of effective school health programs, because waiting until they are older lowers the risk of unintended pregnancy and sexually transmitted diseases, according to the U.S. Centers for Disease Control.

For years, health surveys have found Hawaii youth are less likely to be sexually active than adolescents and teenagers nationwide, and some credit for that success must go to public school sex-ed programs that emphasize abstinence while also providing medically sound information for students who are sexually active or contemplate becoming so.

So the state Board of Education has stumbled by imposing on all regular public schools a new sexual-health education policy that downplays the importance of abstinence, potentially risking the well-being of Hawaii youth in the process.

It is not too late for the board to improve this new policy, which it approved only last week and which the Department of Education has yet to implement.

Policy 103.5 succeeds in ensuring that students receive effective education to protect themselves and others from HIV and other sexually transmitted infections, unintended pregnancy and unhealthy, violent or coercive relationships. But it should be revised to elevate abstinence as the best path to those positive outcomes.

The board could easily achieve this by restoring language similar to that in the old policy but stricken from the new one: verbiage that promotes abstinence as the most responsible choice — not just the surest — and encourages even youth who have had sex before to avoid engaging new partners.

Doing so would follow CDC recommendations that sex-ed programs address the needs of youth who are not sexually active as well as those who are, and recognize that most Hawaii youth are not — a finding reinforced yet again in the most recent Youth Risk Behavior Surveillance System (YRBSS), compiled by the CDC.

The 2013 survey found that only 36 percent of Hawaii high-school students had ever had sex, compared to 46 nationally. Only 4 percent became sexually active before age 13, compared to 5.6 percent nationally. And less than 8 percent had had four or more partners, compared to 15 percent nationally.

That is not to say that all is rosy for Hawaii youth. The minority who are sexually active engage in some risky behaviors at higher rates than their continental U.S. counterparts. They were much less likely to use condoms, slightly less likely to use any form of birth control, and slightly more likely to be victims of sexual violence.

Other studies highlight relatively high rates of teen pregnancy and chlamydia among Hawaii youth.

Delaying sexual initiation, reducing the number of sex partners and frequency of unprotected sex and increasing condom use all reduce serious health risks for students, according to the CDC. All those facts make abstinence a medically sound alternative that should be promoted for the good of Hawaii’s young people, not simply the preference of religious groups on moral grounds.

By downplaying its importance, the BOE understandably raises the hackles of critics who question what message the board is sending. Although recent controversies surrounding sex-ed in Hawaii have centered on the inclusion of material aimed at gay youth, or those with same-sex parents, that is not the issue here.

Same-sex marriage is legal in Hawaii, putting heterosexual and homosexual couples on the same legal footing. It should go without saying that sex-ed curricula will be updated for relevance in this new era.

Abstinence is a message that should resonate among heterosexual or gay, lesbian or transgender young people alike, especially those who are not sexually active and would welcome encouragement to remain that way. The BOE should reinforce that message.

Another weakness in the policy is that it requires schools to post a description of the sex-ed curricula for parents to review before any instruction begins.

A description isn’t good enough. Pono Choices proved that.

The entire curriculum should be available for review, and parents should be wary if schools, the DOE or the BOE resists this necessary transparency.

The BOE crafted this new policy largely behind closed doors and rebuffed the DOE’s suggestions that it specify that sex-ed be for grades 7-12 and that students opt in to the program, rather than opt out.

All of this fuels some parents’ concerns about the BOE’s intentions, worries that could have been allayed had the board met the CDC’s standard recommendation that any school-based HIV, STD and teen-pregnancy-prevention education "be developed with the active involvement of parents and be locally determined and consistent with community values."

This top-down policy fails that standard, and must be improved.