DR. LORETTA Finnegan's crusade was born in the winter of 1969 when she was a young pediatrician working in the intensive-care nursery of the now-defunct Philadelphia General Hospital.

She was stabilizing a premature baby girl and noticed that the infant was shaking uncontrollably. She remembered a tip from a professor: If a baby is shaking, check the mom for tracks, because she might be addicted to heroin.

Finnegan went to the nurses' station and asked to see the mom.

"The nurse told me, 'She's gone. She went out to get a fix,' " she recalled.

"Well, you could have just blown me over," said Finnegan, who grew up in Burlington, N.J., an only child of a meat cutter and homemaker, who married a fellow med student at 23 and had five children by the time she turned 28.

She tried to find all literature written about the effects of heroin on infants. Nothing.

In the meantime, she was caring for more hospitalized babies with similar symptoms, all going through withdrawal.

Six weeks later, the mom returned.

"Her baby was out of any trouble and doing well and growing," she said.

Finnegan told the mom - who had been using heroin for almost 20 years - all the struggles her baby had endured and explained that most were due to heroin exposure in utero.

"I told her she shouldn't use heroin. It was the 'Just say no' attitude. She looked at me and said, 'You're right, doc. I ain't going to take those drugs no more.' And I believed her. That's how naive I was," she recalled.

The mom didn't reappear for another two months - this time, high.

Finnegan figured that to help the babies, she had to start with the moms. She took the then-innovative approach and administered methadone to some pregnant women addicted to heroin. It kept them off the streets.

She applied for and received numerous research grants and soon became a national and international pioneer in the field. In the early 1970s, she was an unconventional woman blazing ahead in an unconventional world.

Over the years, she has helped thousands of babies overcome withdrawal from heroin and other opiates including OxyContin, Percocet and Vicodin. Most babies born in withdrawal are premature.

She developed a detailed 24/7 scoring/assessment tool for the babies, giving doctors a road map to treatment. Specialists record the babies' behaviors and severity of symptoms. They note the length of time the babies are calm or asleep and agitated or inconsolable.

Based on the scores, doctors can determine how much and how often to give the babies morphine. They then slowly wean them off before they are discharged.

The method is widely used in neonatal intensive-care units in the U.S. and abroad.

Finnegan knew since she was 12 that she wanted to be a doctor. "I always felt like I wanted to help people," she said.

Her dad wasn't amused. "He said, 'You're a girl. A girl is a nurse,' " she said.

This was her response: "But I want to give the orders," she recalled with an impish smile.

In 1972, Finnegan founded and directed a landmark program, the Family Center, for drug-dependent moms and their babies. Practically every clinic in Philadelphia began to send pregnant heroin users to her.

The comprehensive center, still running at Jefferson University Hospital, has obstetricians, neonatologists, pediatricians, social workers, psychologists and nutritionists among other specialists.

"Addiction is a chronic, relapsing disease," said Finnegan, sitting on a floral couch in her four-bedroom Avalon, N.J., condo where she lives with her four small, beloved lapdogs.

"You can get better, but relapse is expected . . . The people who do not have compassion and understanding don't know what this disease is all about."

In 1990, Finnegan joined the National Institutes of Health, where she held numerous positions, including senior adviser on women's issues.

"I figured I could do more to help women and children at a federal level than running my clinic," she said.

She retired from the government in 2006, but stays busy as a consultant.

She continues to give presentations at conferences and symposiums.

"Just in October, I was on 12 airplanes and in five cities," she said.

Over the years, Finnegan has dozens of success stories of moms who were able to stay off drugs, get jobs and raise their children.

But the mom who launched Finnegan's career had a different outcome.

The mom couldn't kick the heroin high. She lost custody of her children. It's unclear if she's dead or alive.

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