Harvard and Radcliffe are not reproducing themselves.

That's the report of a survey of American university graduates by the Population Reference Bureau, which warns that America's intellectual upper class is in danger of dying out.

But things are picking up, especially at Radcliffe. The average graduate of the 'Cliffe Class of 1923 has had only .87 children, while the typical Class of 1938 graduate has already surpassed this with 1.18 children, and bids fair to achieve the 2.1 births which the Population Bureau feels is necessary for a class to reproduce itself.

At Harvard, the Class of 1923 is doing twice as well as its Annex counterpart, but the Class of 1938 is proving less successful than its Radcliffe opposite number. The Class of 1923 has achieved a total of 1.73 children per graduate; the Class of 1938 a total of 1.05.

The chief reason for the radical shift in Radcliffe figures, according to the survey, seems to stem from the trend in Radcliffe marriages. Only 59 percent of the 'Cliffe Class of 1923 is married, while 72 percent of the Class of 1938 has already achieved marital bliss.

Fertility Soars

A rise in Radcliffe fertility is also recorded. Ninety-one percent of the Class of 1938 marriages have proved fertile, according to Population Bureau statistics, while the corresponding figure for the Class of 1923 is but 78 percent.

The figures are compiled each year by Miss Betty U. Kibbee, research assistant to Dr. Clarence J. Gamble, a graduate of the Harvard Medical School, who heads the Population Bureau's college department.

Miss Kibbee graduated from Vassar in 1941. "Each year I pray that Vassar will show up well in the figures," she says. So far, Miss Kibbee's prayers have been granted. According to her statistics, Vassar always ranks among the top six women's colleges in the country in its childbirth index.