Fully 10 percent of the women giving birth to premature babies at D.C. General Hospital are alcoholics, according to the preliminary results of a study by a medical anthropologist.

Dr. Margaret Boone's finding of alcoholism in 10 percent of the mothers of babies with very low birth weights compares to a figure of only .9 percent alcoholism among mothers delivering babies of normal birth weight at D.C. General, the city's public hospital.

Testifying yesterday before the House District Committee's subcommittee on fiscal affairs and health, Boone said she found the mothers of the babies weighing less than 3.3 pounds were also more likely to be smokers and less likely to have received prenatal care than the mothers of babies of normal weights.

Among Boone's specific findings:

Eighty-seven percent of the mothers of normal-weight babies said they had received at least some prenatal care, while only 74 percent of the lower-weight group had had any such care.

By the time they were an average of 23 years old, 41 percent of the mothers of the premature infants had been pregnant at least three times, while only 26 percent of the other mothers had been pregnant that often. In addition, 14 percent of the mothers in the premature group had been pregnant more than seven times, while only 4.8 percent of the normal group fell into that category.

About 50 percent of the mothers of the babies weighing less than 3.3 pounds smoked, while only 38 percent of the normal birth-weight group were smokers.

Boone has a doctorate from Ohio State University and has worked for the House Select Committee on Population.

She told those attending yesterday's hearing -- whose subject was infant mortality in the District -- that "one interpretation of high black infant mortality is that it represents a type of selective infanticide, and is the result of the structure of social inequality in the United States, based partly on race, but broadly on economic factors."

The anthropologist's references to "infanticide" and "population regulation" visibly upset Rep. Millicent Fenwick (R-N.J.), one of two members of the committee present, who said the concept of infanticide "strikes me with horror . . . [it's] the most disgusting thing I've ever heard of," she said.

Boone stressed that she does not think such "population regulation" is a conscious policy, but said in an interview afterwards that "our society happens not to give the poor access to proper medical care, and one of the results is that more black babies die."

Boone, who is working at D.c. General as part of the National Science Foundation's public service residency program, said, "These kinds of social options are rarely made consciously, and can be seen easily only as demographic trends in retrospect. There can be no 'fault' assigned in such a case, the system being simply the 'best adaptation' possible in the circumstances."

Yesterday's hearing came a day after D.C. Mayor Marion Barry announced that the city had a 1979 infant death rate of 21.6 per 1,000 live births, a decline of 16 percent from the previous year's 25.8 deaths per 1,000 births.

Almost a dozen local and federal officials appeared before the committee yesterday, with city officials, such as James Buford, crediting the Barry administration with the sharp decline here in the infant mortality rate.

Some medical experts, however say that while the city's various initiatives will most likely have a long-term effect on lowering the rate, last year's decline was most likely largely coincidental. They said it will be several years before the true effect of the city campaign can be seen.