"In this unpredictable world," wrote urbanist Herbert Gans in 1968, "nothing can be predicted quite as easily as the continued proliferation of suburbia."

For 12 years Gans has been right.

But as we enter the unpredictable world of the 1980s, it seems reasonably safe to predict that urban sprawls will at last be contained.

The suburbs will consolidate. The center cities will recover and again become predominant in their metropolitan regions.

Some older suburbs, notably around Chicago, have already stopped growing.

The federal government no longer gives money for shopping centers or highways that are likely to hurt downtown business.

When the 1980 Census forms, which we will receive March 23, are tabulated, they are likely to confirm a drop in the birth rate and an increase of the age group that tends to prefer sidewalk cafes over backyard barbecues.

More than half of America's women work now, but few of them get much help from their men with the household chores according to a study by the Lincoln Institute of Land Policy. That gives them little time and less inclination to travel suburban distances to shop or drop off Baby at a day-care center.

Most important, perhaps, it is reported from all over the country that Ayatollah Ruhollah Khomeini has forced the American people to take the energy crisis seriously. Bravely singing "Don't fence me in," we must huddle together for warmth.

What with Proposition 13, local governments are unlikely to float new bonds for new roads, sewers, water mains, schools, libraries and all the rest. Even the promise of new industry is not apt to over come their reluctance.

Nor will the federal government continue to encourage suburban sprawl, which is now officially recognized as a major case of America's high energy consumption. Rep. Henry S. Reuss (D.-Wisc.), chairman of the House subcommittee on the city, starts hearings next week on "Compact Cities."

The Reuss committee is likely to lead to federal measures that lure and compel new households and new jobs away from the outer fringe, back to the city and to the inner suburbs, where there is still plenty of space.

Many Americans will not like it. This country is traditionally anti-city. Ten years ago half the citizens polled by George Gallup said they preferred to live in a small town or on a farm. Only a third actually did. They had no choice.

And there can be no question that the shrinking of our resources and the resulting higher costs will further restrict our freedom of choice about where and how to live.

Previews of the 1980 Census indicate, however, that there is a new generation of Americans who need not be coaxed into city life. They are the young professionals often without children and with a good deal of disposable income, who are rehabilitating old houses from Boston's Back Bay to San Francisco's Western Addition.

To the delight of some and the resentment of others, they are "gentrifying," as the ugly and somewhat inaccurate term has it, deteriorating inner city neighborhoods.

Gentrification, apparently, is not a passing fad. It is sustained by what suddenly appears to be our largest age group, people who are 30 to 34 years old. They consitute 36 percent of the total population of some 222 million Americans, according to Census previews.

This "middle-age spread," as demographers call the group, is the result of the post-World War II baby boom. Ungratefully, however, the boom babies are presenting us with a baby bust. There is a sharp decrease in the birth rate.

Ten years ago the average American household consisted of 3.1 persons. Now it has 2.8 persons.

But while households have become smaller, there are more of them. There is a vast increase in the number of one or two-person households. Young people move away from home earlier than they used to. More people live together. More couples split and live apart. More elderly people live independently.

The growing number of small households requires a growing number of small apartments or townhouses rather than the large, detached single-family houses suburbia traditionally supplies.

Since most new householders have no children, most do not need the schools, playgrounds, backyards, cul-de-sacs, exclusive settings and other child supports suburbia was invented for.

Not having children to bring up, the new householders, furthermore, can spend more of their income on themselves. George Greer, the urban research specialist, estimates that thirtyish nonparents have, on the average, $750 a year more money to spend than thirtyish parents.

"That is why we have all that spending in the face of a recession," says Greer. "Economists don't seem to understand that."

The spending, according to many indicators, is mostly on culture and travel. It accounts largely for the incredible blossoming of the Clubs Mediterranee, of theater, ballet, opera, concerts, art galleries, good restaurants, special food and wine -- to say nothing of paint removers, brass hardware and other paraphernalia of old-house restoration.

The disposable income of the new householdres if further substantially increased because a majority of women have changed their primary jobs. They manage household consumption, chauffeur children and act as neighborhood volunteers as a secondary occupation. Census previews show that 57 percent of all women between 18 and 64 years old now work outside the home. By 1990, the figure may well be 75 percent.

"A women's place is in the city," says Gerda R. Wekerle in a recent report of that title for the Lincoln Institute of Land Policy at Cambridge, Mass. Wekerly maintains that despite fulltime employment, women still have the primary responsiblity for child care and housewowrk. Even women who have college-educated men in the house are left with 80 to 95 percent of the routine household tasks.

Nor do they have the use of cars to the extent men do.

With the entry of women into the labor force, Wekerle says, "Levittown will not survive." Women require an enriched environment for their expanded roles. They want to minimize commuting and have shopping, child care and recreation close to their homes. They are joining pressure groups against exclusionary zoning and for new opportunities for variety and choice.

Working women, says Wekerle, "are a major impetus for gentrification."

Because of this impetus, because the new life-style of the new householders tends toward city living rather than the old suburban dream, center cities, which have been losing population, are likely to be repopulated in the 1980s.

"The cities will become younger, and the suburbs will become older," observes Thomas Muller, an economist and research associate of the Urban Insitute. With the new householders, civic leadership will return to the city.

In sum, strengthened cities in the 1980s will be brought into better balance with perhaps somewhat weakened but more stable and less exclusive suburbs.

And this, in turn, should create a better political climate than we have now for regional cooperation to deal not only with the energy problem, but also with the physical and social ugliness of our urban environment.