Facts are sometimes the first casualty in the abortion debate.

Take, for example, a committee hearing at the Utah Legislature in January on a bill that would increase the criminal penalty for illegal abortions and change the definition in Utah law of just when a fetus is viable outside the mother's womb. The law passed both houses and awaits Gov. Jon Huntsman's decision whether to sign it.

During that hearing, Rep. Stephen Sandstrom, R-Orem, observed, "We're not talking about preventable pregnancies now. ... If you look at the statistics across this country, the vast majority of abortions happen to middle-age women. These are women that know about birth control. It doesn't have anything to do with teaching abstinence in the schools."

Rep. Sandstrom was flat wrong, not least about the age of the "vast majority" of women who obtain abortions performed in Utah. The latest statistical report on abortion from the Utah Department of Health's Center for Health Data covers 2007. Of the 3,516 abortions performed in the state that year, the largest number were obtained by teenagers. They underwent 1,162 abortions. (The report divided the patients into age groups covering five years.) The next-highest number went to women ages 20-24, who underwent 1,125 abortions. Together, these two youngest cohorts accounted for 65 percent of the abortions performed that year. In all, women under 30 accounted for 89 percent of all abortions in Utah.

So much for middle-age women.

Because most women who have abortions are young, we continue to believe that one of the surest ways to reduce the number of abortions is through comprehensive sex education in the public schools that includes instruction about contraception. A bill proposing that curriculum went nowhere in this year's legislative session.

Other statistics in the abortion report also lead us to argue for comprehensive sex education. Some 60 percent of the women who had abortions had never been married. So, while Utah's abstinence-only sex education is correct when it teaches that not having sex before marriage is the certain way to prevent pregnancy, it also is clear that that message is not persuading many young people.

Leaving them ignorant of the knowledge to protect against conception and disease from sex outside of marriage is both cruel and unrealistic. What's more, it is bad public health policy.

Abstinence is one way to prevent abortion. Contraception is another. Utah should teach both.