Bills that would require seat belts or infant seats for young children riding in automobiles in Maryland -- one of at least 22 states now considering such laws -- appear to be dead for this session of the General Assembly, apparently because of a lack of public interest.

Maryland's proposed child-restraint laws, which are backed by doctors and a wide variety of state and federal officials, also appear to be grimly supported by new state studies on infant deaths in motor vehicles.

Maryland infants under a year are considered six times more likely to be killed in traffic accidents than children between the ages of one and 14, according to a study just published by two Maryland professors.

The high traffic death rate of Maryland infants, the study says, can be correlated directly with the lack of seat belts and child restraints -- 86 of the 89 children under 15 killed in Maryland crashes between 1973 and 1977 were not using seat belts or infant car-seat restraints.

Of the three wearing belts, two would have been killed in any case because the car compartments were crushed, the study said. The third, a child in an infant seat, was not properly belted in.

At least eight of the 89 deaths were of babies cradled in their parents' arms or held on laps, according to professors Susan P. Baker of Johns Hopkins University and Jerome J. Karwacki Jr. of the University of Maryland. In most of the cases, the parents' own bodies crushed their children against dashboards.

Infants are particularly vulnerable because of the softness of the brain and skull during the first months of life, the study notes. About 75 percent of 89 children killed suffered severe heead injuries.

The authors were pessimistic about increased voluntary use of seat belts and child restraints, although seat belts already are installed in most cars and most child restraints can be attached to them. Other studies have found that seat belts are unused by as many as four out of five drivers. Even among the few drivers who use seat belts for themselves, only about 25 percent use seat belts for their children.

For example, a 1975 study by the Insurance Institute for Highway Safety found that in 5,000 car crashes in which at least one child was a passenger, 93 percent of the children were unrestrained. And the few instances where seat belts or infant seats were used, more than 75 percent of the restraints were fastened incorrectly.

The Baker-Karwacki study urges additional legislative and educational efforts to increase use of car restraints, as well as use of automatic crash protection, such as padded dashboards and air bags.

The sponsor of one of the two child-restraint bills introduced into the Maryland House of Delegates, Idamae Garrott (D-Mont.), attributed the failure of her bill to "a cautious judiciary committee which probably doesn't want to get too far ahead of public opinion."

Garrott said little public interest had been generated in the matter this year, the first year in which a child-restraint law had been proposed in Maryland. But, she said, there had been strong support from doctors and most government agencies, including the Maryland State Police and state department of transportation, as well as virtually all federal and private highway and safety organizations.

Garrott's bill would require children to use seat belts or infant seats, and to ride in the back seat whenever possible.

No federal laws requiring child-restraints have been proposed in Congress, and only one state -- Tennessee -- has enacted a state law. The Tennessee law went into effect in 1978 and already has increased seat-belt use by children from 9 to 30 percent, according to the National Highway Traffic Safety Administration. Tennessee now requires all children under 4 to be restrained when riding in cars.

For children aged 1 to 15 in Maryland and across the country, traffic accidents have long been the leading cause of death -- exceeding all childhood diseases, drowning and fire, according tto the National Safety Council.

The most recent national statistics on traffic deaths show that 49,510 people, of whom 4,614 were children 14 and under, were killed on U.S. roads in 1977. While cancer -- the second leading killer among children -- caused 1,733 deaths of children between the ages of five and 14, traffic accidents caused 3,142, almost twice that number.

A separate study in the December issue of Pediatrics magazines claims one reason for the continuing high death rate for children in traffic accidents is not just the failure to use car restraints for children but their incorrect use, bad design and a general public confusion "as to just what is the best way to restrain the child while riding in the automobile."