Among the more curious statistics to have emerged here shows that Poland under martial law scored the highest birth rate in Europe.

Some wags around Warsaw are suggesting that the evening curfew imposed in the first months of the military crackdown last year, and the general lack of public entertainment possibilities once the curfew was lifted, had something to do with the baby boom.

Historical researchers, though, have observed that when Poland's communist allies suffered similarly bleak conditions--Hungary in 1956 and Czechoslovakia in 1968--the number of babies born went down sharply.

"Why does everything here among us Poles have to be different and surprising?" asked a youth magazine, Razem, in a lengthy article that tried, with exasperation, to explain the accelerated national birth rate.

The baby curve actually started turning up during the heyday of the now outlawed independent trade union Solidarity, before the Dec. 13, 1981, imposition of martial law. These "Solidarity children," as the newborns of that period are sometimes referred to, could be explained as products of the optimism and enthusiasm prevailing in those times.

More perplexing is why the birth rate continued to climb during the dark, repressive months that followed, when dreams of a freer Poland dissolved.

Add to that the deep distress and hardship that many Poles endure now just trying to feed the mouths already around the supper table--not to mention the chronic shortages in baby items ranging from diapers to toys--and the decision to have larger families appears even more bewildering.

According to the government's report on the social and economic situation in 1982, published last weekend, 370,000 babies were born last year. This works out to an average 10.2 babies per thousand Poles, the report says, and adds that was the highest birth rate in Europe. Poland's current population is 36.4 million people.

The new infants are not the children of Poland's postwar baby boom. That crowd started appearing about a dozen years ago.

A 1981 change in the maternity-leave law, lengthening leaves to three years and authorizing special-care bonuses, may have provided some encouragement. But the bonuses are not very generous.

Perhaps the babies attest to the growing influence of the Roman Catholic Church, with its opposition to abortion and birth control. Interviews in the Polish press with some mothers suggest that a strong factor is a focus on family, a widespread turning inward by many Poles--to their homes and blood ties--as a source of comfort and security. "In the face of exceptional economic difficulties," concluded the magazine Razem, "people start to become convinced that the basic value is home and family, where a person feels secure, where he knows there is someone who is close and loves him."

The baby thus becomes an antidote to despair and a source of fulfillment in a country where coveted items--cars, apartments, trips abroad--seem unattainable. "A child does not have competition; it is a value in itself. It is the only value that can be owned without money," said Razem.

ECONOMIC REFORM, the theoretical if not yet realizable aim of the government of Gen. Wojciech Jaruzelski, is forcing many top officials to relearn the principles of management they were once taught.

To show the government is serious about reform, 2,914 senior bureaucrats were required to take a test on basic elements of the new economic program. The exam results, reported this week, indicate that the idea of decentralized authority is catching on at the top, but slowly.

"Perhaps no other single undertaking related to reform gave people as much thrill as the recent 'class test' on the reform's detailed provisions," reported the government daily Rzeczpospolita.

For more than three decades, Poles regarded the economy as something planned from above. Now the system is to be shaped by hundreds of independent wage, price and production decisions. Clearly, the change is not easy.

Only 6 percent of those who took the test were considered to have done very well. About one-third scored poorly or unsatisfactorily.

No one got all the answers right. The top scorer was--somewhat reassuringly--Czeslaw Gawlowski, who advises the minister for economic reform.

Of 150 possible points on the exam, the average score was 100. All in all, said Henryk Sadownik, deputy director of the management institute that reported the results, the outcome was better than expected.

But the grades left room for wondering how those down the line will manage if many senior officials fail to grasp the principles of the economic reform. Another 12,000 employes at the local and regional level will take their turn at the test in coming months.

THE NONHAPPENING of the week was the opening Monday of what had been advertised as Poland's first sex shop.

But there was nothing sexy about the new place on Bednarska Street in central Warsaw. Despite the ads for pink panties and flowered garters, it offered second-hand clothes.

The hoax was perpetrated by the editor of the consumer weekly Veto, who lamely defended the false advertising as "a kind of survey to determine whether there is a demand, at least in a part of society, for 'intimate articles.' "

Pornographic material is rare and expensive in Poland. A sizable crowd of all ages that showed up the first day was none too happy to learn the truth.

"If this is a joke, it's not very funny," said a lady dressed in fur. "Jokes can be played on April 1, but not in the winter when there's an underwear shortage."