A 1 pound, 1 ounce infant born 18 weeks prematurely has survived for almost two months in San Diego. She may be the smallest baby known to have survived such a premature birth.

The doctor caring for Ernestine Hudgins, who now weighs 1 pound, 14 ounces, said she has a 95 percent chance of survival.

"She is very special," said Dr. Morton L. Cohen, medical director of the neonatal unit at San Diego's Children's Hospital. "Her lungs should not have been developed at all, and her brain should not have been developed to the point where it could tell her to breathe."

The unprecedented survival of the child, born to San Diego housekeepers Gloria Patterson, 27, and Ernest Hudgins, 24, is expected to fuel controversy between pro-abortion and anti-abortion groups.

Ernestine was born after only 22 weeks of gestation. This is six weeks earlier than the 28-week point of "viability" suggested by the U.S. Supreme Court as the stage when the government might begin to regulate abortions.

"Viability is only dependent on the extent of the sophistication of the medical equipment available to keep these kids alive, and this goes to prove it," said Dan Donehey, spokesman for the National Right to Life Committee.

According to a spokesman for the American College of Obstetricians and Gynecologists, "There is no unambiguous documentation that an infant born weighing less than 601 grams at a gestational age of 24 weeks or less has ever survived." Ernestine, however, weighed 484 grams at birth, and both her mother and Cohen said today they were certain of the gestational age of 22 weeks.

Cohen cautioned against using Ernestine's case to justify massive efforts to save other children born prematurely. A baby born 17 weeks prematurely and also weighing pound, 1 ounce survived in San Diego in 1978, Cohen said, but remains severely retarded.

Cohen said Ernestine at birth in most ways fit the profile of an infant her age, showing, for instance, no calcification in her bones since that process begins at about 25 weeks.

However, her lungs were unusually well developed. He said she has developed chronic lung damage characteristic of premature babies, but the damage is considered minor. She is being kept on a respirator and is being fed high-calorie formula through a tube in her stomach.

Cohen said she would remain in intensive care for at least two more months, but so far gave every sign of developing into a normal child.

Patterson, Ernestine's mother, said in an interview that she was in pain the day before her baby's Feb. 8 birth and went to Sharp Hospital. The doctor there told her to expect a miscarriage, but she insisted on staying at the hospital. The child was born at 8:30 the next night.

The baby was transferred to Children's Hospital the next day, and doctors told her the chances of survival were not good.

"But she's still here," Patterson said, "and I am real happy."