One of the more sordid aspects of the debate over the use of Medicaid funds for abortion is the argument over what it may cost the taxpayers. It is a narrow and mean approach to a problem that ought to be settled on larger and more humane considerations, such as fairness, non-discrimination and the commenweal.

In both the House and Senate, the anti-abortionists have repeatedly emphasized that Medicaid is now paying for about $300,000 abortions a year at a reputed cost of around $50 million. What an "imposition on the taxpayers" is the refrain. Sen. Orrin Hatch (R-Utah) said he discerned a "remarkable similarity between those who believe in abortion and those who are spending us into bankruptcy."

The weakness of this argument is that it invites a devastating rebuttal: If the conflict is going to be reduced to what is best for the taxpayers' pocketbook, that pocketbook could be a hundred times worse off if the drive to curb abortions among the poor succeeded in spawning a legion of additional candidates for the welfare rolls.

Dr. Louis Hellman, former Deputy Assistant Secretary of the Department of Health, Education and Welfare, says it is "wishful thinking to believe that the federal cost will be reduced if Medicaid abortionbs are eliminated.

"It has been estimated," he says, "that prenatal care, delivery and the first year of the baby's life cost approximately $2,200. The cost of raising a child to 18 years in a low-income family has recently been estimated at $35,261."

It doesn't take a mathematical genius to figure out what the ultimate cost to the taxpayers would be if several hundred thousand of the pregnant poor were annually denied abortions, with the result that they and their unwanted offspring went on welfare for years on end. It could make the amount now spent on Medicaid abortions look like tip money.

Nevertheless, it is all too clear that the anti-bortion lobby has, temporarily at least, got the politicians on the run. the latest vote in the Senate was a case of pure panic. Last year over two-thirds of the Senate (57 to 28) voted against banning Medicaid funds for terminating pregnancies. Last week it reversed itself by a vote of 56 to 42, although not a single new argument was introduced in the debate.

Naturally, the "pro-file" lobby is momentarily euphoric, for it mistakenly believes it has won a major victory. Actually, it has won a very limited one, for over 75 per cent of U.S. abortions are performed on those who can afford to pay for them, and even their pregnancies, even if they have to butcher themselves, as they once did.

The ultimate hope of the police groups - to wipe out all abortions - is a pipe dream. Even if, improbably, they should somehow succeed in putting over a constitutional amendment outlawing every form of abortion, the result would doubtless be a repetition of the country's disastrous experience with prohibition, which turned Americans into a nation of scofflaws, thousands of whom died from drinking wood alchohol or worse.

Abortion (legal or otherwise) is here to stay - and grow - not only in the United States but all over the world. The trend toward legalization is unmistakable, even in countries such as Italy and Israel where religious opposition has stoutly resisted it.

Several months ago, despite organized resistance by the Vatican and the governing Christian Democrats, the Italian Chamber of Deputies passed a bill that would give Italy one of the most liberal abortion laws in Western Europe. In effect, it would permit abortion on demand for any woman over 16.

More recently, the Israeli parliament passed a similar bill, notably liberalizing the legal requirements for terminating pregnancies, a reform fiercely opposed by the Orthodox Jewish bloc. The new law simply recognizes the realities in Israel, where recent studies showed that 46.7 per cent of all Israeli women have had at least one abortion by the time they reach 40.

Canada, long an anti-abortion stronghold, is also changing. In March the Canadian government, in a major policy shift, called on the 10 provinces to establish special abortion clinics, with the federal treasury sharing the cost. Canada is still a distance from abortion on demand, but reform is making conspicuous gains.

One reason most women want the right to a legal abortion is that it is nine times a safer than childbirth, according to a federal study covering 1972 through 1974. The study, recently reported in the Journal of the American Medical Association, also found that the death rate for legal abortions was below that for the removal of tonsils or appendix.

Last year, legal abortions in the United States increased by 8 per cent to 1,115,000. Deaths associated with these terminations were merely 2.6 per 100,000, down from 4.1 per 100,000 only three years earlier. About 25 per cent of the women who terminated pregnancies were married.