The Food and Drug Adminstration has begun considering measures to regulate the use of caffeine in drinks and drugs if animal tests now under way confirm some previous indications that caffeine can cause birth defects.

Dr. Jere Goyan, FDA commissioner, reported this yesterday to a Washington Journalism Center study group.

The most likely measure, if animal tests confirm caffeine dangers, would be a warning label for pregnant women, Wayne Pine, FDA associate commissioner for public affairs, said. The labels might tell women not to consume caffeine or to consume only moderate amounts in cola drinks and stay-awake drugs. And they might warn them of the danger of consuming too much caffeine in coffee, tea, cocoa and chocolate while pregnant.

"We are only now considering" these and other possible regulatory options, however, Pines said, and they are contingent" on results from tests on rats due to be completed in six to eight weeks.

Even if these results seem adverse to caffeine, he said, it could take some months for scientists to review all the evidence. Goyan would then discuss the regulatory options with Health, Education and Welfare Secretary Patricia Roberts Harris, Pines said, and any proposals for regulation would have to be published in the Federal Register to allow a period for public comment.

What this means, in effect, is that no regulation or warning could be issued until 1981 at earliest, Pines said.

Goyan's comments yesterday were nonetheless the furthest any FDA commissioner has gone in indicating that some action on caffeine may prove necessary. He said the agency is concerned about scientific reports of birth defects in the offspring of animals fed caffeine, and will be required by law to try to reduce any dangers if these effects are confirmed.

Most of the adverse effects observed so far have been in animals. But there have been some reports of abortions, stillbirths, and premature births among women who drank six to eight cups of coffee daily.