Seven newborns lie sleeping, swaddled in pink and blue blankets and tucked into bassinets in a hospital nursery. Six were born to mothers addicted to crack cocaine and then abandoned.

In the same pale yellow room with green curtains, a 6-month-old girl smiles and gurgles in a swing near two children in playpens. They, too, are "boarder babies," whose addicted mothers abandoned them.Hospital officials say boarder babies like these at Howard University Hospital are taking up space that could be used for treating sick children.

"Sometimes there's not a vacant bed in neonatal intensive care between Richmond and Philadelphia," says hospital director Dr. Haynes Rice.

"See that," he says, pointing to the baby in the swing, right next to the infants. "You shouldn't have them with newborns. But what can we do?"

The material cost for dealing with these children is high - from $750 a day to $1,768. The physical and psychological price is immeasurable.

Statistics gathered by the House Select Committee on Children, Youth and Families suggest that 375,000 newborns a year may be harmed by drug exposure and that last year 11 percent of pregnant women used drugs.

Although hospital officials say the number of boarder babies is growing, the problem is so recent that nationwide statistics aren't available. There's not even a standard definition, although Rice defines boarder babies as infants who are ready for discharge but have not had a parental visit for 30 days.

A recent visit to the Howard hospital found 21 of the abandoned children. They appeared healthy, although some had been born drug-addicted.

"Healthy is a word I'd be careful about using with these children," Rice says. "They're not sick, but some of them will have problems later on. We're told these babies will have problems for the rest of their lives."

Two of the recent infants tested HIV positive, meaning they carry the virus believed to cause AIDS.

In the typical case, a multiple drug user gives birth, stays for three days and goes, leaving behind what Rice calls "these little itty-bitty ones."

The sign on the nursery door says: "Daily visiting hours restricted between 10 a.m. and 12 noon." But the only visitors many of the infants have are the busy nurses who tend to them when they can.

On another floor, an 11-month-old boy, the oldest boarder baby at the hospital, sits in a carriage eating ice cream in a pediatrics ward covered with wallpaper of clowns and Raggedy Anns. The nurses call him by his name, Terrail, but to hospital officials he is "Baby 3." A sick child wails in the background.

Terrail is not ill but already is developmentally handicapped by a life spent entirely in the hospital. The shortage of staff means he can't crawl and play as youngsters his age normally would, and the nurses say he hasn't taken any steps toward walking.

"It's wrong for a baby to be in a hospital for a year and not sick," Rice says.

Hospitals must swallow the cost of caring for the boarder babies, an expense that eventually is passed along to the public through higher fees and insurance premiums. Meanwhile, hospitals appeal to the welfare bureacracy to find homes for the children.

Nationally, boarder babies' fates vary by circumstance and jurisdiction. After 11 months, Terrail has not been placed for adoption or foster care.

After 30 days the Howard hospital notifies the District of Columbia Department of Human Services about the abandoned children. But the babies wait as forms are filled and papers are processed.

Out of desperation, Rice joined with the department to place ads in local newspapers asking people to "please open your home and heart" and adopt or take in one of the children. In the first three days, the department received 30 inquiries.

But ad responses alone are unlikely to keep pace.

In California, for example, the foster child population increased by 28 percent from 49,978 in December 1986 to 64,900 in December 1988.

And as many as 60 percent of drug-exposed infants end up in the foster care system, says Neal Halfon of the Children's Hospital in Oakland.

"The dramatic increase in crack cocaine use is mirrored by increases in the number of foster children," he said. "An already bad situation is becoming disastrous."