Pat Tompkins, head of the office of maternal and child health for the D.C. government, eyed a weight scale at the Congress Heights public health clinic. A young woman, in her twenties and eight months pregnant, crossed her fingers, but the news was not good. Expectant mothers are supposed to gain weight to avoid producing babies so small that they must struggle to survive. Low birthweight is the primary reason for the city's high infant mortality rate, but this young woman had lost 10 pounds during her pregnancy.

"How much milk are you drinking each day?" Mrs. Tompkins asked.

"I don't like milk," the woman said. "It has to be strawberry or chocolate or I won't drink it."

Mrs. Tompkins sighed and handed the woman a nutrition pamphlet. "Everybody we've seen tonight has lost weight," she said.

The Congress Heights clinic sits on troubled ground in Southeast Washington. On one side is Condon Terrace, one of the city's most notorious cocaine markets. In a nearby 20-block area, 20 people were murdered in just nine months of drug gang rivalry. Also near is Valley Green, a subsidized housing complex where residents and police are battling a resurgent drug trade.

Drugs, of course, have a lot to do with the problems the clinic deals with. Last Thursday, two women walking out of the clinic, both of whom had overcome substance abuse, were arguing knowledgeably over the FBI drug "sting" of Mayor Marion Barry after watching the videotape on TV. "He didn't go there for drugs. You know what he went there for," one said. "Naw," replied the other, "you saw him take that hit. He didn't gag. He didn't cough. He knew how to smoke."

On Wednesday evenings, after the clinic's regular staff has retired, some of the city's highest-ranking public health officials join with other volunteers to work without pay at Congress Heights. They keep the clinic open until 8:45 p.m. in an effort that began under former health commissioner Reed V. Tuckson and continues under his successor, Dr. Georges Benjamin.

If you want to know why this city has such a high infant mortality rate, or why the life expectancy of Washington blacks is far below that of their national counterparts, a visit to the clinic provides a few answers. Rae K. Grad, a registered nurse and executive director of the National Commission to Prevent Infant Mortality, saw an example one night.

"At least four patients who were well into their pregnancies were diagnosed with new cases of venereal disease," Mrs. Grad wrote in a journal she keeps on her clinic experiences. "Their partners are not getting treated and are re-infecting the women. All the women explained that saying 'no' to their partner was out of the question, getting the partner to come in for treatment was out of the question -- macho image and all that -- and using {protection} was a dubious possibility."

On another Wednesday night, Grad recalls, a frantic 17-year-old mother brought in a baby who was vomiting frequently. The mother simply had no idea about the digestive capacity of newborns: her baby boy was vomiting because he was literally drowning in formula.

On the maternity side of the clinic, one finds women who lack the basic information and support systems that so many more affluent women take for granted. In that sense, the clinic volunteers have roles that go beyond nursing duties and extend to serving as mentors, friends, teachers.

"The {patients} leave here encouraged," said Lenard Harrison, who drives volunteers to and from the clinic on Wednesday nights. "But they still have to go home to all their problems. Sometimes they can't keep up."

There are similar problems on the medical side. Marlene Kelly, chief of the city's ambulatory care clinics, is another of the Wednesday night volunteers. Diabetes, hypertension, and arthritis are among the most common ailments she sees. The problem she often faces is that the patient isn't focusing on his or her illness.

"Some come in very depressed. They are inundated with problems. They are more concerned about being evicted, the fact that they aren't earning enough money; they are upset about a relative who is in jail, someone close to them who has been shot," Dr. Kelly said. "You have to make contact with the patient on that level first before you can focus in on their blood pressure. Then you have a better chance of helping them."

One example was the couple whose electricity had been turned off because of unpaid bills. They came to the clinic and said that an electric company employee had told them that the power would be turned on immediately only if a doctor confirmed that the unpredictable seizures suffered by the husband constituted a real medical emergency. One of the clinic's doctors made a telephone call, and the electricity was back on that night.

Once, the city had the resources to keep two clinics open for evening hours, but D.C. government budget cuts have meant that city health officials can no longer afford to pay the overtime required to keep the clinics open at night. The volunteers remain.

The writer is a member of the editorial page staff.