The new World Bank report on population growth makes for sober reading. It concludes that unless strong action is taken to reduce fertility rates in developing nations, the world's population will more than double by the year 2050 - from 4.8 billion people now to about 10 billion then.
That in turn, says World Bank president A. W. Clausen, poses an ''unacceptable situation'' for economic growth in developing nations and would ''mean lower living standards for hundreds of millions of people.''
What is important to understand about future population growth is that such estimates need not be taken as firm predictions. As pointed out by Mr. Clausen, they are based on what might happen, ''given reasonable assumptions'' about current family planning programs, the number of women of childbearing years, etc.
Thus, they serve as warnings to the world community to consider the importance of family planning - and the unfortunate impact that unchecked population growth could have on future economic development. Considered in this light, the World Bank conclusions, and other, similar reports, should serve a useful purpose in renewing the commitment of developing nations to family planning. Eighty-seven nations in the developing world, representing roughly 95 percent of its total population, have publicly funded family planning programs. With small increases in funding for such voluntary programs, population growth projections could be reduced.
Still another element warrants attention - what could be called the ''ingenuity'' factor - the ability of mankind to intelligently produce unanticipated answers to future problems.
Considered in technological terms the space-age world of 2050 will surely be far different from the world of 1984 - at least as different as the world of 1984 is different from the world of 1918. Saying this is not to be naive about the long-range consequences of not encouraging comprehensive family planning programs. Such programs are essential. But how many experts, 50 or 60 years ago, could have foreseen that Singapore, Taiwan, or even Japan, for that matter, would today be global leaders in commerce and industry? That Brazil, despite current unemployment challenges, would post both rapid economic growth and population growth? That a region of the United States like New England, ''written off'' by many experts because of its loss of traditional industries such as shipbuilding and shoe manufacturing, would have a renaissance in high technology? In short, then, a sense of proportion seems in order as nations and individuals rightly go about the task of reconciling population growth with future economic development.