One of the most detailed studies ever undertaken of the District of Columbia's high infant mortality rate has revealed that 15.2 percent of the mothers of infants who died in 1976 had no prenatal medical care.

The study also shows that infant mortality has declined dramatically in the past 10 years in the Shaw area of inner Northwest although it still remains very high.

The infant mortality rate has remained consistently high during the past 10 years in the far Southeast area of the city where there are few city health facilities and only a handful of private physcians.

The infant mortality rate in the city in 1976 was 24.9 deaths per 1,000 live births, compared to a rate of about 14 deaths per 1,000 live births for the nation.

A recent study showed wide disparity between black and white infant mortality rates in the city, with 27.7 black babies dying for every 1,000 born, while there were only 7.5 white infant deaths per 1,000 births.

The study prepared by Dr. Armand Pulcinella, whose work is financed by the Robert Wood Johnson Foundation, shows that the infants mortality rate in the Shaw area declined from 44.2 deaths per 1,000 births in 1965, to a rate of 25.5 in 1972. In 1976 the rate was back up to 30.3, a fact Pulcinella says he cannot explain.

One possible explanaton for the decline in infant mortality in that area, known as service area 6, is that it was part of the model cities program of the late 1960s, and received federal funds for clinics and health services.

The situation in that area, which houses some of the city's poorest residents, is still bad, with residents having 11.6 percent of the babies born in the city in 1976, and 14.2 percent of the infant deaths.

The area of Southeast Washington south of Pennsylvania Avenue SE had an infant mortality rate of 26.1 in 1965, and had a rate of 29.2 in 1976. However, said Pulcinella, when the annual statistics in that area are averaged they show no change over the 10 years.

Pulcinella also found that teen-age pregancies contributed only a small percentage to the infant mortality, despite the fact that teenagers have a much higher percentage of high-risk pregancies and low-birthweight infants.

According to Pulcinella, the data shows that even if all the deaths of babies born to teen-agers could be eliminated, the city's high infant mortality rate would decline only 3 percent.

Pulcinella said he believes his study shows that it is not sensible to set up separate programs to deal with pregnant teen-agers.Rather, he said, steps should be taken to include them in regular prenatal programs.

The far Southeast area, the least medically served in the city, accounted for 23.5 percent of the city's births in 1976, and 27.5 percent of the infant deaths.

According to Pulcinella's study, 23.2 percent of all births to teen-agers in the city occur among residents of that area and 27.4 percent of the low-birth-weight babies in the city were born to mothers from those neighborhoods.

There are only two city clinics with obstetrical services in that area of Southeast and no obstetrical clinics at Hadley Memorial or Greater Southeast Memorial Hospitals, the two serving in that area. There are a total of eight private physicians in the area who provide obstetrical services for Medicaid patients, five of them in the soutbern part of the region and three of them located along the northern boundary.

Pulcinella said the data presented yesterday to D.C. City Council member Polly Shackleton and city officials responsible for maternal and child health, represents tht first part of a two part study.

Pulcinella said he will now attempt to compare the mothers of infants who died with a matched group of mothers whose infants did not die.