A year after a controversial new law liberalized West Germany's previously strict abortion codes, about 50,000 women a year still find it easier to cross into the Netherlands for a quick one-day abortion with few questions asked.

They go because the new West German law - is proving hard to implement.

Although many women are, surveys show, taking advantage of the new provisions, thousands of others are bewildered and frustrated by the technical difficulties of getting an abortion approved and bitter at the embarrassment of having to explain to so many people why they want it.

Furthermore, the new law has unlocked a new range of personal and professional questions that are also tormenting many of the doctors and counselors who are supposed to help carry out that law.

Indeed, of all the major Western industrialized societies that have been wrestling with the question of abortion laws in recent years, West Germany may be the most fascinating.

The Germans - perhaps not surprisingly - have probably gone further than any other country in trying to pin down in precise legal terms everything about abortion. The highest constitutional court here has even sought to define when life begins.

That court also pointed out that Germany's bitter experience with Nazism is also a factor, leading to a greater requirement to protect unborn life here than in some other Western countries.

Its reasoning on the subject ran counter to much of the reasoning in American courts, according to an American legal scholar, and was based on different factors. In particular, it held that a fetus is entitled to the protection of the West German constitution from the 14th day after conception. Thus, the new law strives to deal with abortion as a matter affecting two citizens' rights, not those of the mother alone.

Two world wars have left this country of about 61 million with more women than men, and more women voters - 54 per cent of the electorate.

West Germany is also split between generally liberal Protestants in the north and conservative Catholics in the south, with the Protestants slightly more numerous.

Both factors have been central to the fierce partisan political battle that has raged here for several years over abortion. Both also probably figured in the razor-thin federal election victory last year by a Social Democratled coalition that favored liberalizing the laws over the Christian Democrats, with strong ties to the Catholic Church and the anti-abortion forces.

The law passed June 21, 1976, permits abortions during the first 22 weeks of pregnancy if doctors determine that the child will be deformed. Abortion can be prescribed during the first 12 weeks if the pregnancy is due to rape or if it is shown that the woman would undergo extremely severe "social distress from the child's birth.

An abortion could also be ordered at any time if it were proven that the woman's life or health was in danger.

Before the new law, only clear danger to the life or health of the mother justified legal abortion.

For the abortion-seeking West German woman, however - typically unmarried, between 15 and 25 years old and work-class - there is a huge step between law and reality.

First, the approval of two doctors is needed, one to verify that the women qualifies for a legal abortion and a second one willing to do the operation.

In some predominantly Catholic areas, town councils have forbidden hospitals to carry out such operations, an as-yet-unsolved dilemma in West Germany's system of 10 relatively autonomous federal states.

Many doctors are Catholic and oppose the reform on religious grounds; many others, Health Ministry officials say, are conservatives and refuse to perform the operation.

Some 45 per cent of those seeking legal abortions here are doing so on the "social" grounds, an extremely difficult area to make judgments on, officials say.

West Germany has hundreds of counseling offices, but women who come in claiming to have financial or marital problems or simply to be unable to handle a baby emotionally are frequently offered help - child care or a bigger apartment - but told not to have an abortion.

"Many women resent this," says Elke Keinath-Vogel, member of a commission trying to analyze the effect of the new law. "They don't like being dependent on finding someone who agrees with them. It is only the woman who can really know how she feels and what she needs.Even the counselors don't like to talk to them, because it puts them in an impossible situation of judgement.

For young women who live outside the major cities, finding advice - particulary in conservative areas - is still hard. It is even harder and frequently too embarrassing for the woman to find two doctors in the same town without compromising her privacy.

A recent television film showed a young woman hoping to keep anonymity, walking from one doctor's door to the next seeking approval for an abortion.

So, Keinath-Vogel says, the trains to The Netherlands still carry many women willing to pay between $110 and $180 for an abortion there.

Ironically, those abortions are illegal under Dutch laws, but West German officials say that the Dutch government does not enforce the restrictions and an abortion business thrives all over The Netherlands, including the capital.

Furthermore, The Netherlands rate of medical complications following abortion operations is the lowest in the world, officials here say.

Before the new law, about 65,000 West German women a year made the trip to The Netherlands, according to Dutch figures. Thus, the new law appears to have cut the number of West Germans going elsewhere for abortions. Besides the 50,000 going to The Netherlands, a smaller number go to England, which has more liberal laws, than West Germany.

Justice Minister Hans-Jochen Vogel has estimated that under the old laws, some 300,000 illegal abortions were carried out here each year, but Health Ministry officials say this figure is too high. They estimate that some 200,000 West German pregnancies now end in abortions of all kinds - legal and illegal - each year. West Germany had some 602,000 live births last year.

In neighboring Austria - a predominantly Cotholic country where a new law more liberal than West Germany's took effect in January 1975 - there were 65,000 legal abortions that year compared to only 90,000 births.

In Kenaith-Vogel's view, there is enough public support in West Germany for even more liberal abortion laws, but the matter is so intensely political and caught in so many conflicting north-south regional traditions that more changes are uncertain.

Another key factor is that the women's rights movement here is less advanced than in other Western countries.

Two years before the new law went into effect an even more liberal reform bill was passed, but this was subsequently rejected by the constitutional court.

It was that court decision in February 1975, however, that laid out legal distinctions that have attracted such wide attention among scholars, especially because it is contrary to much reasoning in American court.

The West German Court stuck exclusively to constitutional issues and did not rule on the basis of traditions or religious factors.

Thus, it invoked that section of West Germany's postwarconstitution, which says that "Everyone shall have the right to life . . ."

The judges went on to define life "in the sense of the historical existence of a human individual" as existing "according to definite biological physiological knowledge from the 14th day after conception."

Thus, "everyone," in this constitutional context, meant unborn as well as born life.

Nevertheless, the court pointed out that protection of unborn children cannot be ordered regardless of the costs to the mother, and it basically ordered the parliamentarians to go back to their desks and come upwith a new law that more adequately balances the constitutionally protected interest of the unborn child with those of the mother, both of whom are entitled to "human dignity" under the West German constitution.