An estimated 50 million abortions -- half of them illegal -- are performed around the world each year and as many as 200,000 women die from them, according to a study released yesterday.

The Worldwatch Institute said in its report that restrictions on pregnancy termination do not curb abortion rates, they only cause more deaths -- most of them in Third World countries.

But Douglas Johnson, legislative director for National Right to Life, the nation's leading antiabortion group, called the report a "very polemic document" and said it lacked independent research.

The Worldwatch Institute, an independent research group funded by private foundations and United Nations organizations, said the number of deaths from illegal abortions could be far higher than its statistics show because many go unreported and accurate figures from developing countries are difficult to obtain.

The author, Jodi L. Jacobson, said the best way to reduce the number of abortions and related deaths is to make abortion a legitimate family planning component.

She said the rate of abortion has dropped quickest in countries where legalized abortion has been included in family planning programs.

But Johnson said "all of the empirical evidence" shows Jacobson is wrong.

"In every nation that's legalized abortion, you get a vastly greater number of abortions. That's true in the United States," he said.

The study said available data show that in nations where abortion is legal, pregnancy termination ranks fourth among the types of birth control, after female sterilization, intrauterine devices and oral contraceptives.