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Extreme Preemies

Babies born at 23, 22, even 21 weeks gestation are testing the limits of modern medicine. As two local families learned, they bring complications and questions about when is too early to deliver.

Jacob Stewart, one of the youngest patients earlier this month at the Floating Hospital for Children at Tufts Medical Center, was born at 24 weeks, 5 days of gestation. Here, a foot monitor measures the oxygen level in his blood. Jacob Stewart, one of the youngest patients earlier this month at the Floating Hospital for Children at Tufts Medical Center, was born at 24 weeks, 5 days of gestation. Here, a foot monitor measures the oxygen level in his blood. (Photo by Channing Johnson)
Email|Print|Single Page| Text size + By Dr. Adam Wolfberg
April 27, 2008

IT WAS HER TURN TO LIE ON THE NARROW BED IN THE DIMLY LIT ROOM AND WATCH THE GRAINY IMAGE of the child within her slide around the ultrasound's screen. Apparently done, the sonographer left the room and returned with the physician. The fetus was fine, but they were worried that her cervix was dilating prematurely. On what was supposed to be a good day, Misty Cheney, a 35-year-old assistant bank manager with an open, honest demeanor, was sent right away to Tufts Medical Center in Boston for further evaluation. Over the next 24 hours, the doctors ruled out all possible explanations for the Lowell woman's premature dilation. She wasn't in labor, but her cervix was 2 centimeters dilated when it should have been closed.

Her physicians expressed pessimism as they stood around Misty, who lay in a bed tipped head down to recruit gravity's help in keeping her fetus inside. Lacking other options, Misty and her husband, Jay, a 37-year-old handyman, chose to proceed with the placement of a stitch around her cervix that might help keep it closed and protect the pregnancy for at least a few more weeks.

But the next day, while Misty was still in the hospital, the stitch failed, and with a devastating gush of warm liquid running down her legs, her water broke.

Dr. Linda Kleeman, an obstetrician, presented the stark facts to Misty. She was 20 weeks into her pregnancy, halfway to full term. Most obstetricians and pediatricians don't consider pregnancies viable until 24 weeks, Kleeman explained, when a fetus has matured sufficiently to have a reasonable chance of surviving. (Not coincidentally, 24 weeks is the gestational age when abortion becomes illegal in Massachusetts and most other states.) It was unlikely that Misty could remain pregnant for four weeks without her amniotic fluid, and even if she did, without that fluid, her baby's lungs might not develop sufficiently to breathe.

"After her water broke," Jay remembers, "we just assumed it was over."

Kleeman recommended inducing labor to end the pregnancy and to minimize Misty's risk of developing a dangerous infection. An intravenous line was put in place and pitocin dripped in to cause Misty's uterus to contract and expel the pregnancy.

Kleeman's recommendation and the Cheneys' decision were unimpeachable: No reasonable physician would suggest that a baby born at 20 weeks (when it is typically the size of a chicken breast) could survive. Before reaching 24 weeks, a fetus is limited by the fundamental immaturity of its organs, such as the lungs, kidneys, and skin. Nevertheless, medical advances have prompted many to ask if 24 weeks is as hard and fast as once thought. Could the threshold be pushed to 23 weeks, or even earlier? The most authoritative report to date, published two weeks ago in The New England Journal of Medicine, describes a modest survival rate at 23 weeks and even some survivors at 22 weeks. And then there was Amillia Sonja Taylor, a Florida girl born after just 21 weeks and six days of gestation, weighing less than 10 ounces and measuring 9 1/2 inches long out of the womb. When she was discharged from a Miami hospital in February 2007, four months after her birth, her story attracted worldwide attention and mesmerized the public. Amillia's doctors and parents spoke of her survival as a "miracle" and described the minimal consequences of her prematurity, along with the prediction that she would have a relatively normal childhood. She celebrated her first birthday last October.

The stakes for determining a minimal gestational age are unbelievably high. There is the matter of life or death for these babies. And those who survive, along with their families, communities, and schools, will have to grapple with potentially lifelong disabilities. Then there is also the political dimension, as defenders and opponents of abortion use these babies as examples in the battle over the right to terminate pregnancies at a gestational age where survival just might be possible. In a city that has some of the most innovative neonatologists in the world, the question of when newborn viability does and should begin - the question suddenly facing Misty and Jay Cheney - is being more closely watched than ever.

IT WAS THE MORNING OF FEBRUARY 17, 2007. Even though Misty Cheney's nurse had steadily increased the pitocin through the night, Misty didn't feel so much as a cramp, and having spent the night thinking and anguishing, she and her husband had more questions about their unborn daughter, who would be their first child. Jay explained: "I kept asking the nurse and the resident . . . 'What if she does cry?' 'What if she does breathe?' 'What if she looks like she might survive?' " With such important questions unanswered, the pitocin was stopped, and the on-call neonatologist was paged. Dr. John Fiascone, a kind man with an easy smile, specially trained to care for premature neonates, knows better than most the challenges that very tiny babies face. Jay then asked the hardest question: "If she struggles to survive, will you do what you can?"

Fiascone told Jay and Misty that, typically, at least half of babies born at 24 weeks survive. He explained that at the Floating Hospital for Children at Tufts Medical Center (like most of the specialized newborn intensive care units in Boston), about one-quarter of babies born at 23 weeks survive. He also brought up a critical point that is often overlooked by women and their partners who are at risk for bearing an extremely premature child: that most children who survive deliveries this early in pregnancy have lifelong problems - cerebral palsy, diminished intelligence, lung diseases, as well as more subtle issues like learning disabilities. At 23 weeks, Fiascone said, of the 25 percent who survive, only one-third end up being healthy, relatively normal kids. Fiascone assured Jay and Misty that he would examine their daughter at birth, and if there was evidence that she might survive, he would attempt to resuscitate her. But with gestation at 20 weeks, he could not give them meaningful hope.

As recently as the 1970s, most babies born before 28 weeks died. Since then, technological innovations, new drugs, and increased knowledge have dramatically decreased mortality for premature newborns. Most importantly, the widespread use of steroid injections for women at risk of premature delivery has meant that newborns delivered early are hardier, increasing their chances of surviving.

Fetal lungs may challenge neonatologists more than any other organ. Week by week, large blood vessels and air channels weave and intertwine, branching from the large into the microscopic. By full term, a collection of tiny air sacs, each surrounded by microscopic blood vessels, is found at the end of each branched air channel. Here, two cells separate blood from air, and the tiny sacs comprise, collectively, an enormous pliant surface that facilitates the exchange of life-sustaining oxygen and carbon dioxide waste. Before this dance is complete, the air sacs are undeveloped, impenetrable layers separate air from blood, and the gas exchange required to sustain life cannot occur.

Sent home on doctor-prescribed bed rest, Misty counted the hours and days that she remained pregnant, hoping to eke out enough time so that their baby might have a chance. Flipping television channels, Jay encountered the story of preemie Amillia Sonja Taylor, who was then heading home from the hospital. Pretty soon, Jay's cellphone was ringing with calls from friends encouraging Misty and him to "hang in there," because if Amillia could survive, their child could, too. "You can imagine how we felt," remembers Jay. "They had a 21 week baby, and they were going home. Maybe we could do that, too."

Amillia's doctors claim certainty about her gestational age at birth, because she was the result of in-vitro fertilization and thus the exact date of fertilization is known. However, most neonatologists and obstetricians remain steadfastly skeptical. For doctors who spend days and nights struggling to coax life into babies born too soon, the concept of a 21-week newborn surviving defies their fundamental understanding of newborn physiology. They worry that Amillia's story gives false hope to desperate parents like Jay and Misty. Some physicians also worry that any evidence of survival at this early gestational age will provide ammunition for abortion foes who might use Amillia's story to argue that gestational-age limitations on abortion should be moved earlier in pregnancy - from 24 weeks to 21 weeks, or even earlier.

MOST EXPERIENCED NEOnatologists have faced a desperate couple, about to deliver a newborn at 21 or 22 weeks, and promised to evaluate their baby at birth to see if it can be rescued, only to find that, try as they might, they cannot force air into the baby's stiff lungs. The futility of these attempts has prompted many newborn intensive care units during the past decade to develop policies that help doctors decide which babies to try to save and which to let die. A few doctors will try to resuscitate all babies, but many draw the line at 24 weeks. They consider any pre-24 week survivors - who nearly always suffer significant brain injury or other abnormalities - to be rare exceptions to the rule, a combination of 24-weekers masquerading as more premature babies due to uncertain gestational ages, and babies preternaturally mature, who defy the odds and survive thanks to luck.

"There is a point below which we will say no to resuscitation," explains Dr. Steven Ringer, chief of newborn medicine at Brigham and Women's Hospital in Boston. But Ringer acknowledges that use of a sharp line can become absurd. "What do you tell the woman who is in labor at 11:45 p.m. on the evening prior to reaching 24 weeks?" he asks rhetorically. "Just cross your legs?"

However, neonatologists - including Ringer - are extremely reluctant to eliminate these policies, because they believe that they do a disservice to those children who are resuscitated at birth and end up surviving with devastating neurological injuries. "If I don't resuscitate, then I fail the parents," Ringer says. "If I do resuscitate, have I failed the baby? And, therefore, have I failed myself?"

Dr. Jonathan Davis, director of newborn medicine at the Floating Hospital for Children at Tufts Medical Center, feels similarly: "To me, the injury rate in these very little kids is so high that in many instances I just can't justify resuscitation."

Ringer isn't sure that the goal of increasing survival before 24 weeks ought to be a high priority. "We have advanced science to where survival is reasonable at 24 weeks," he says. "But morbidity is still very, very high. I think where we are working now is trying to make every baby born at 24 weeks do well. I'm not sure we need to be focused on advancing the point of survival further forward in time. It might be possible, but it would require a quantum leap."

While the lung is architecturally exquisite - perfectly branching air chambers delicately surrounded by vascular structures that exchange oxygen and carbon dioxide with maximum efficiency - the placenta is somewhat more crude, a redundant and inexact organ. Its vessels invade the uterine lining parasitically, exchanging gas and nutrients without elegance. It is this relative structural simplicity that Dr. Joseph Vacanti, surgeon-in-chief of the Massachusetts General Hospital for Children, found appealing when he was considering how he might take the quantum leap that Ringer describes.

In his lab, Vacanti's group works on developing artificial organs. His most ambitious project is to create an artificial placenta modeled on the liver his lab has under development. The substitute liver looks like a stacked set of glass cocktail coasters, with tubing emerging from opposite corners. The lab has pioneered use of the etching equipment that draws microscopic circuitry on silicon computer chips to cut tiny channels into plastic plates. When the plates are put together, the etched channels form carefully designed networks of artificial blood vessels that are the central building block of the lab's organs. "You design a vascular system," explains Vacanti, "then you grow liver cells on top of that. Then you have a liver, so to speak." In tests, Vacanti's liver has generated enthusiasm by performing some basic metabolic functions of a human liver.

The goal of the placenta project is bold: to design an organ that could be attached to a newborn's umbilical cord, providing oxygen, nutrients, and waste removal until the baby's lungs can take over the task. Vacanti envisions extremely premature neonates - or even full-term babies with lung disease - attached to the artificial placenta by their umbilical cord after delivery.

Replacing the placenta and tricking the fetus into remaining a fetus, instead of helping the premature newborn adapt to the hostile world outside the womb, is such a radical approach to the problem of extreme prematurity that it challenges the prevailing belief that developmental limitations create an insurmountable barrier to advancing survival earlier in pregnancy.

The artificial placenta, however, has a long way to go. Vacanti's team of young researchers is only beginning to consider major physiological challenges that must be overcome before animal studies could start. Blood, for example, pumped into the placenta would promptly clot without the addition of thinners, and yet blood-thinning medications cause hemorrhages in the brain and lungs of preterm newborns. Vacanti's idea is to populate the etched channels with a single layer of endothelial cells - the same cells that naturally line blood vessels and prevent clots from forming there, making blood thinners unnecessary. However, when asked how to get endothelial cells to uniformly line the etched channels, the researchers in Vacanti's lab shrug and smile.

THE IMPROBABLY NAMED GRACE KELLY struggled to transition from fetal to newborn function. Several times daily, a physician would lean over Grace and listen to her heart, the bell of the tiny stethoscope still covering most of her chest, and listen for evidence that Grace was becoming used to life outside her mother's womb. Three weeks earlier, on December 1, 2006, Christine Kelly, a 40-year-old petite homemaker from Whitman, got up to pee and felt panicky realizing the sweet-smelling liquid running down her leg was not urine, but amniotic fluid. Christine was 23 weeks pregnant - three weeks further along than Misty Cheney had been when her water broke.

At South Shore Hospital in Weymouth, the on-call obstetrician confirmed that Christine's water had broken and offered Christine and her husband, Scott, a stark choice: The staff could give Christine medications to make her go into labor, and her baby would die, or she could go into Boston to see if anything else could be done. "It was pretty much a no-brainer," says Christine. "I had to give that baby a chance. I probably gave the induction-of-labor option a thought for about half a second. Then I looked at Scott, and it was clear he agreed."

An ambulance brought Christine to Tufts Medical Center, where she met a neonatologist. As Christine remembers: "There were numbers and percentages about survival rates and injuries, and I heard about brain bleeds, cerebral palsy, blindness, and deafness. I had to literally say, 'Stop.' I asked her to tell me about what was going to happen right now. I didn't want to know about what was going to happen tomorrow. I wanted to focus on keeping this baby inside of me." Christine, like Misty, was told that if she delivered at 23 weeks, Grace would have a 25 percent chance of surviving and would probably be impaired in some way. But every day that Christine remained pregnant, the numbers shifted in their favor.

Occasionally, doctors present their gloomy statistics about premature newborns and find parents who don't want to take the risk of having an injured child and instead choose to end the pregnancy before 24 weeks. (In their hearts, many physicians who have seen the worst of prematurity sympathize with these patients.) But mostly the doctor's warnings are met with blank stares, or even anger, and expectant parents choose to hold on to the hope that they will hit the prematurity jackpot and take home a relatively normal baby. "I have come to the conclusion," admits Fiascone, who counseled Misty and Jay Cheney, "that even when you explain to parents that the chance of survival without major injury is a very low percentage, most of them still want you to do everything you can to resuscitate their baby."

Doctors believe it is their duty to give patients like Misty and Christine a balanced perspective on their predicament, and many feel obligated to offer an abortion, even though they know the overwhelming majority will turn them down. Necessary as they feel it is, many obstetricians and neonatologists feel almost cruel as they bombard parents with statistics and chilling details about the awful injuries that their premature child may struggle with for his or her entire life - injuries that can neither be predicted nor prevented.

These dismal warnings had little effect on the Kellys. Christine and Scott, a 39-year-old facilities engineer at Genzyme, considered what the pediatricians had told them. "I thought I would bring home a disabled child," says Christine. "I was prepared for blindness, deafness, cerebral palsy. I said to Scott, 'How do you feel about a baby who is blind or deaf?'"

"We can do this," Scott had said.

"People live with disabilities every day," she says. "I'll learn sign language. I'll learn Braille. Scott will build a wheelchair ramp."

In their neat home in Whitman, with an above-ground pool stuck in a corner of the yard and Tyvek paper still wrapping the three-season porch that Scott winterized in his spare time, the Kellys are hands-on people. "We were willing to take home a disabled child. But we did not want her to be severely brain damaged. We would take cerebral palsy or blindness, but we did want her to be able to have a high quality of life."

When Christine finally went into unstoppable preterm labor at 24 weeks, and her cervix dilated completely, the nurses and doctors in the darkened labor room encouraged her to push. "I just wanted to keep her inside me," Christine remembers. She pushed four or five times, and Grace was born, weighing 1 pound, 6 ounces. A tube advanced into Grace's trachea fed oxygenated air in and out of her lungs, lamps overhead radiated heat, catheters - snaked into her umbilical vessels before they clotted closed - provided nutrition and fluids. And remarkably, two days later, it seemed that of the severe problems that so often kill tiny babies quickly - intracranial bleeding, overwhelming infection, and intestinal death - none had visited her.

There were setbacks, but Grace grew. She started to breathe on her own, began feeding, and gained weight. In March 2007, she was transferred to a hospital closer to home, and eventually, four months and eight days after her birth, joining the minority of babies born at 24 weeks who do not suffer obvious injuries, Grace went home. She joined her brother, Sean, who's now 3.

On a sunny and hot afternoon last summer, Grace sat suspended in a battery-powered seat that rocked her back and forth as she dozed. She had grown since coming home but still required several medications, and she had been re-admitted to the hospital once after coming down with a viral infection that most kids fight off with ease. It will be years before Christine and Scott know whether Grace will have trouble in school, or need corrective eyewear, or have mild permanent lung disease. But it seems that no matter how quality of life is defined, Grace will have that.

While Grace Kelly defied the odds, the outcome for Misty and Jay Cheney's premature baby - stillborn after 20 weeks and five days gestation - was more common.

Jay tells the story of his own father, born two months prematurely in 1932. He draws the parallel between the doctors who cared for his grandmother and the doctors who took care of Misty. "They tried to tell my grandmother to give up on that pregnancy - that my father would never survive. Now survival after seven months of pregnancy is no problem. . . . Maybe 20 years from now, 21 weeks will be the way seven months is now."

In the living room of the Cheneys' Lowell town house, near the television that sits in the corner of the room, is a mahogany box containing items from the near life of their daughter, whom they named Natalie. Regularly, Misty takes out the satin-covered "memory box" that the nurses gave her, along with the photos of Natalie and some dried flowers. When she reads the obituary from the Lowell Sun, she remembers the service held on a cold Saturday on March 3, 2007, in a little chapel on the grounds of the Lowell cemetery where generations of Cheneys are buried. In this family plot, next to Jay's great-great-grandmother and another child who had died at 22 days of life in a generation past, Natalie was laid to rest.

Dr. Adam Wolfberg is an obstetrician at Tufts Medical Center in Boston. E-mail him at awolfberg@tuftsmedicalcenter.org.

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