Patrick McFillin was a micro preemie, weighing 1 pound, 6 ounces, when he was born in September, after his mother had been pregnant for just 23 weeks.

"And three days," Kimberly Pawlowski McFillin is quick to add.

At that stage of development, at the very edge of hearing doctors gently suggesting it may be time to give up hope, every day matters.

Patrick now weighs more than 13 pounds and is doing well, but the Bucks County boy is an exception. Most babies born before 24 weeks of gestation do not survive, and those who do usually — but not always — suffer serious, lifelong disability.

That is why his mother and others in the close-knit community of preemie parents are especially interested in the latest research from Children's Hospital of Philadelphia. Scientists there gained international headlines last week for inventing an artificial womb, keeping extremely premature lambs alive inside a fluid-filled bag for up to a month until they could survive on their own.

Physicians say it will be three to five years before they are ready to try such an approach on human babies. When they do, the effort will be aimed at critically premature infants just like Patrick: those born before 26 weeks.

The goal is to cocoon them for just a few weeks, getting them to an age when most children survive and the risks of complications — brain bleeds, lung problems, grave infections, to name a few — are sharply reduced, said team leader Alan W. Flake, a fetal surgeon at Children's.

"If you can get them to 28 weeks or so, you remove most of the risks of prematurity," Flake said in a conference call with journalists.

Parents in the preemie community have been eagerly sharing the news and asking themselves the question: If the artificial womb were available to them, would they have been willing to try it for their babies?

McFillin, of Richboro, thinks she would, having seen what it was like for her son's fragile body to undergo a barrage of medical treatments in the four months he spent in the neonatal intensive care unit at Abington Hospital-Jefferson Health. Patrick is the youngest of four; his oldest brother is McFillin's child from her first marriage, to Philadelphia Police Officer John Pawlowski, who died in the line of duty in 2009.

She does think the idea of a baby immersed in fluid may take some getting used to.

"It's futuristic," McFillin said. "It will be strange for parents to see their baby inside."

kimberly pawlowski mcfillin
Patrick McFillin spent 115 days in the intensive care unit at Abington Hospital-Jefferson Health.

Wyndmoor residents Paul and Martha Sharkey, who had extremely premature twins in November 2010, also said they would have been game. The couple experienced both the heartbreak and the hope of prematurity, as daughter Claire survived while her sister, Mary, died of an infection after two weeks.

If anything could have improved Mary's chance at life, they would have tried it, they said.

"We think it's amazing," Paul Sharkey said of the artificial womb project.

Flake and his colleagues say further tests on animals are needed to ensure that such a procedure would be safe. And the eventual device for humans would be far different from the assemblage of parts used in the laboratory, some of which came from Home Depot.

The Children's Hospital researchers envision a self-contained unit fashioned with medical-grade plastics, with an internal audio system that would play a recording of a maternal heartbeat, among other refinements.

The umbilical cord would remain attached to the baby on one end, while the other end would be connected to an external oxygenator within a minute or two after birth. The infant would then be immersed in a bag of fluid, allowing further development of the lungs.

(Chronic lung disease is one of the most common complications of extreme prematurity; the organs are not fully developed at that stage of pregnancy, and further development stops once the lungs are exposed to air.)

Having the new option would dramatically alter the decision-making process for parents of extreme preemies, who grapple with grim odds. A recently published New England Journal of Medicine study tracked outcomes for 12 years, reporting that by the last four years of the study, more than a third of infants born at 23 and 24 weeks survived — though four out of five were developmentally impaired as toddlers.

Physicians must maintain a delicate balance in guiding parents through such statistics, said Brownsyne Tucker Edmonds, an assistant professor of obstetrics and gynecology at Indiana University School of Medicine.

"How do you continue to hope alongside them for the best possible outcome but help to start preparing them for the more probable outcome?" Tucker Edmonds said.

children's hospital of philadelphia
Researchers at CHOP kept extremely premature lambs alive in fluid-filled bags until the animals were developed enough to survive on their own. The team hopes to try an "artificial womb" with human infants within three to five years.

In its most recent guidelines, the American College of Obstetricians and Gynecologists says resuscitation of the newborn is recommended at 24 weeks, something to "consider" at 22 and 23 weeks, and "not recommended" at earlier gestational ages.

The decision placed before parents in some ways mirrors the choice that families face with elderly relatives at the end of life. Many families ask physicians to do everything they can to keep the patient alive, while others weigh the odds of survival against the possibility of suffering and disability, and opt for palliative care.

"There isn't any right answer," Tucker Edmonds said. "It's just the answer that's right for you."

The Children's team hopes that the advent of an artificial womb could make that decision easier someday.

Flake, the fetal surgeon who led the team, acknowledged that seeing a baby inside such an artificial womb may be difficult. Parents would receive careful counseling about the risks vs. benefits of such a procedure before they opt to try it, he said.

The system would be designed so that if anything went amiss, the infant could be quickly removed and placed on current methods of life support. That typically includes the use of a ventilator, which keeps an infant alive but often damages the lungs, Flake said.

The artificial womb, on the other hand, would represent a gentler first step before an infant is subjected to the poking, prodding, and lights of the intensive-care unit, he said.

"I'm optimistic that this will actually improve upon what we currently do," Flake said.

The Sharkeys, who started a nonprofit called Today Is a Good Day (todayisagoodday.org) to distribute care packages and information to parents of preemies at several area hospitals, agreed that reducing the need for aggressive treatments would be a plus.

Their daughters were born after 23 weeks and five days of gestation. Claire is now 6 and doing well, though physicians had cautioned the parents she might never walk or talk. But having spent six weeks on a ventilator at Abington, then known as Abington Memorial Hospital, she still suffers from respiratory issues. She uses an inhaler twice a day, and what would be a minor cold for most children often goes to her lungs.

Perhaps a few weeks in an artificial womb would have spared her the need for a ventilator, lessening the risk of respiratory ailments years later, her father said.

"If you're not putting that pressure on the lungs, you would expect better outcomes in most cases," Paul Sharkey said.

Life as the parent of a newborn preemie is bewildering, and a new technology will strike most as just another tool in the high-tech gallery of 21st-century medicine, he and his wife said.

"Parents just want to know, 'Is my baby safe?'" Paul Sharkey said. "Are they being taken care of?"