America has been fulminating for years about the problem of teen pregnancy. Me too. A quick computer search turns up 37 columns in which I mention the phrase. Maggie Gallagher wishes we'd give it a rest.

She didn't say it quite so directly; she's not that rude. What she did say, in an intriguing new "report to the nation" from the Institute for American Values, is that the problems we lump under the rubric of "teen pregnancy" often are about something quite different.

Listen: "The teen birth rate is, and has been for many years, much lower today than it was in the 1950s and early 1960s, when many teens married and began their families young. It is the unwed birthrate that has grown rapidly enough to earn the label 'epidemic.' "

In other words, while we've been harping on "teen pregnancy," what really has been happening is a striking decline in the importance we place on marriage.

But isn't the problem "children having children"? Surely Gallagher wouldn't want us to encourage child marriages. Listen again to what Gallagher, also a syndicated columnist in addition to being on the institute staff, and her research team have to say in "The Age of Unwed Mothers: Is Teen Pregnancy the Problem?":

"The bulk of today's teen pregnancy problem is less 'children having children' than increasing numbers of young adult women having babies outside of marriage. . . . Unwed teen moms younger than 18 account for only 13 percent of babies born out of wedlock.

"As a society, we aim a fair amount of public money and many strong words at the problem of 'teen pregnancy,' that is, at the 376,000 births in one recent year to single mothers under the age of 20. Yet we pay comparatively little attention--indeed it often seems that as a society we are stone-cold silent--regarding the 439,000 births that same year to single mothers in their early twenties.

Are we against the former but indifferent to the latter? If so, what is our reasoning? Consider the prospects for a typical 20- or 22-year-old single mother and her baby. Are they really that much different, or better, than those facing an 18- or 19-year-old single mother?"

Gallagher, like the Manhattan-based Institute for American Values for which she led this investigation, is unabashedly pro-marriage. But that in no way diminishes the validity of her insight: We have, in some important respects, stopped being a marriage culture.

The trend may have begun with feminist (and other) reaction against the teen marriages of the 1950s as "traps." Increases in the divorce rate sparked talk about marriage for the "wrong" reasons. And then, perhaps along with increased career opportunities for women, marriage was spoken of increasingly as a "bad deal" for women. Teen mothers contend, with great earnestness, that they are terrific mothers but too young for marriage; that will come later, they say (though it frequently does not).

Not only has the stigma against single parenthood been greatly reduced (with what unintended consequences?) but, according to Gallagher, professional counselors today frequently advise pregnant young women quite specifically against marrying the fathers of their babies--against falling into the "trap."

The advice turns out to be somewhat less liberating than it sounds. As the report notes, "A young man who gets his girlfriend pregnant, but declines to marry on the grounds that he is too young, will typically enjoy ample opportunities in the coming years, as he 'grows up,' to enter into a lower-risk marriage with another woman.

The same cannot be said for the girlfriend. Entering into single motherhood, as against marriage, is likely permanently to compromise her future prospects for marriage."

Gallagher's contribution is not to recount the well-documented economic arguments against single motherhood but to drive home the degree to which young people's separation of parenthood from marriage reflects an attitude shift in the larger society.

She ends the 50-page report with 16 public policy proposals, of which these two top the list:

"Put an emphasis on marriage, not just age, at the center of all of our efforts and programs in the area of teen sexuality and teen pregnancy," and

"Retire the term 'teen pregnancy' from our public discourse. As a popular name for a serious social problem, the term has outlived its usefulness and now obscures more than it reveals. . . . How about 'unwed parenthood' as a substitute?"