Rosalynn Carter returned to D.C. General Hospital yesterday to help celebrate the first fruits of the $17 million construction project she helped launch there two years ago.

The First Lady cut a ribbon to formally open the new obstetrics and gynecology building, then visited babies in the nursery and admitted the renovated emergency room, where she helped paint a wall just two years ago.

"So many good things have happened here, and I'm just glad to be a small part of it," Mrs. Carter told the crowd of city officials, hospital administrators and employes gathered on the hospital grounds at 19th Street and Massachusetts Avenue SE. She added, "This is not the end of the improvements. This is the beginning."

The dedication of the new facilities, which have been in use for several months, marks a milestone in an ongoing renovation effort. The construction is designed to give the hospital a facelift, but also to correct violations of life-safety codes -- such as inadequate numbers of stairways and fire exits -- that have contributed to D.C. General's failure in recent years to receive a full, two-year accreditation from the national body that reviews hospitals.

The hospital was unaccredited from 1975 to 1978, and has received one-year accreditations since then from the Joint Commission for the Accreditations of Hospitals. The accreditors' 1980 visit occurred last month, and administrators still are waiting for their decision.

Wherever she went, Mrs. Carter marveled at how the newly painted corridors and waiting areas contrasted with her memory of her first visit to D.C. General in March 1978.

"There was really no lobby. A few wooden benches and some concrete dividers served as a waiting room," she said. "Today that's all changed."

In his welcoming speech, Mayor Marion Barry recalled coming to the hospital for his annual physical last year.

"I got good treatment, not because I was mayor but because you all treat everybody that way," he said, adding that it was about time he returned for another checkup.

After the dedication ceremony, Mrs. Carter visited one of the new nurseries and cuddled 6-day-old Rochelle Holmes while she talked with her mother Ann about the prenatal care Holmes had received at a city clinic in Potomac Gardens.

She moved from bassinette to bassinette admiring other babies, including triplets born April 29.

"I love babies like this when they just lie in the bed," she said, stroking one that had awakened and begun to cry. "I don't have one I can cuddle now." o

Then Mrs. Carter walked next door to the emergency room, waving along the way to inmates in the old D.C. Jail who stretched their hands through the barred windows.

In the emergency room lobby, she shook the hands of surprised patients who sat waiting to see doctors in the "walk-in" area. Then she moved on to the hospital's front lobby to greet volunteers and representatives of community groups who have contributed to the renovation effort.

"I have a pinched nerve in my hand, but I took off my bandage so I could shake her hand," said Georgia Williams, an employe in the hospital development department.

Back in the emergency room, patients settled back into the newly upholstered chairs and continued to wait their turn to be seen.

"It looks awfully nice," sighed Alverna Brathwaite, who had been waiting 1 1/2 hours for a clerk to call her to be registered. "The emergency room is connected to the other clinics now."

She realized that in 1977, she had visited an outpatient clinic feeling faint from high blood pressure and had been told to walk all the way around the building to get to the emergency room.

There was no shortcut then.I can remember that."