Marcella Boroli Balestrini, the daughter of a wealthy Milanese businessman and seven months pregnant with her second child, recently spent 54 days knitting white bonnets, little sweaters, and tiny shorts for the child she will soon give birth to.

Nothing out of the ordinary -- except that Balestrini is one of about 45 Italians kidnaped for ransom this year and she did her knitting under an indoor tent, chained by the ankle to a cot.

"For us you are a jewel and we are treating you well in order not to damage you", one of several identically masked kidnapers told her shortly after she awoke from the chloroform they had drugged her with after she was forced into a getaway car.

Her released for a reported ransom of slightly less than $2 million showed once again that for Italian criminals this relatively low-risk crime pays off handsomely.

Italian police, who have been largely ineffective against the kidnapers, fear that kednaping is probably here to stay.

It has become a part of life that the wealthy are learning to live with, particularly here in the rich northern Lombardy area where there have been 83 kidnapings since 1973 and 10 this year.

Because the government spends little money and manpower on the fight against kidnaping, victims' families will have to continue to rely largely on imaginative and skilled intermediaries to bring their loved ones home safe -- and at the lowest possible price.

Gianni Dedola, a lawyer who sereral years ago moved to Milan from Sardinia, is one such intermediary. Since 1975 Dedola has negotiated 10 ransoms, often delivering the money himself, talking for hours on the phone with kidnapers or their agents, and on at least one occasion helping police arrest a suspect.

Dedola, who carries a 38-caliber revolver, was contacted by the Boroli family after his negotiation of another kidnap ransom last summer.

The ninth kidnaping in Lombardy this year, the Balestrini case brought to a head the conflict between victimized families and the authorities. A few days before Balestrini was released, a first ransom payment of almost $3 million was intercepted by police acting on a local magistrate's orders.

Despite suggestions that intermediaries might have arranged the interception either to bring the ransom demands down or to gain time for police investigators, the confiscation set off a furious debate between supporters of a hard line and those who believe such a policy does not work.

Antonio Pagnozzi, Milan's chief of detectives, says the reversal of a policy that forbade police to investigate until a hostage was released, rather than a hard-line policy on ransoms, partly explains why kidnapings dropped substantially last year from the 1977 high of 76.

In recent years police have broken up several kidnap gangs and many families have adopted measures of self-defense. Nevertheless, Pagnozzi says, kidnaping will remain, and combating it is made doubly difficult by the fact that "from the moment that kednaping takes place there is a war on between families and the police."

The families, Pagnozzi explains, fear police investigation will endanger their loved one's lives. Police feel that cooperation can save lives as well as money and make kidnapping less attractive.

Thus police often are forced to the sidelines while delicate strategies are worked out by men who are making a career working in this tragic sector of Italian life.

When Maria Grazia Mazzocchi, 34, was kidnaped last June, the first thing her publisher father, Gianni Mazzocchi, did was to contact Dedola.

For six weeks Dedola bargained, argued and pleaded with Maria Grazia's kidnapers in an attempt to convince the kidnapers that the family would cooperate but that Mazzocchi could not afford to pay a requested $3.6 million.

This campaign involved leaks to the press that the Mazzocchi publishing house was on the skids, Mazzocchi's hospitalization for prostration, and tips that enabled police to confiscate an initial ransom payment.

"It's a dangerous game that can't be pushed too far," says Dedola, whom one kidnaper described as "tough but fair."

"The kidnapers have an ace up their sleeve, the hostage, but we have time on our side," says Dedola, because the longer a hostage is held the greater are the kidnapers expenses and their chances of capture.

Kidnaping, originally a tradition among the bandits of Sicily, has traveled up the Italian peninsula, gradually becoming a major source of revenue for the Mafia and terrorist groups.

Since 1960 close to 600 people have been kidnaped for ransom in Italy, with initial taboos against seizing children or women now long gone.

In August, after 65 days, Maria Grazia Mazzocchi was released in downtown Milan, upon payment of a $1.8 million ransom that was delivered at the 16th stop of a treasure-hunt route.