If you want to clear a room of congressmen these days, all you have to do is whisper "abortion."

That's the technique that foes of birth control are using to block legislation -- such as the domestic family-planning programs supported by Title X of the Public Health Service Act -- that, judged on merit, would enjoy wide support in both parties.

No money under Title X has been used for abortion- related activities for more than a decade. In fact, as senior Republicans and Democrats on the House health subcommittee agree, money spent on family planning is one of the most effective ways of reducing abortions. An estimated 430,000 abortions are avoided in this country each year because of these programs.

Title X has been the target of the part of the anti-abortion movement that also opposes all "unnatural" birth control. Directly presented, this position would win little support in a country in which women use contraceptives widely. So opponents chip away at the programs by offering amendments that they hope will label program supporters as being "pro-abortion" or "anti-family."

One amendment would prevent subsidized family- planning services from being offered in places where abortions are also carried out. This would have little effect on abortion clinics, but it would close down family-planning services at a substantial number of hospitals -- a foolish disruption of useful services.

Another amendment would prevent doctors from discussing legal abortions as an option for patients -- probably a First Amendment violation. Another would require family-planning centers to notify parents if their teen-age daughters seek services -- a rule far more likely to encourage sexual activity than not.

Hoping to avoid a fight, bipartisan supporters of Title X tried last week to bring the measure to the House floor under a procedure preventing any amendments. While the vote won majority support -- which would not have been possible if abortion had really been at issue -- it failed to get the two-thirds majority needed to block amendments. Now sponsors may sidestep reauthorizing Title X and simply continue funding through the usual last-minute omnibus appropriation bill.

Avoiding debate on an easily distorted issue is tempting. But Congress ought to be willing to stand up and be counted on a measure where public support is real. There is wide agreement that parents ought to encourage their children to behave responsibly and that family-planning clinics should, as they do, encourage family participation. But the evidence from this and similar countries shows that wider cultural factors -- and not family planning -- determine the level of teen-age sexual activity, and that family planning is the best way to avoid the sad consequences of much of that activity.