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Aug. 9, 2000 -- In 1963, President John F. Kennedy and his family mourned the untimely passing of their infant son, Patrick. Born nearly six weeks premature, he survived only two days before succumbing to a respiratory infection. If a baby is born today under the same circumstances, he or she has an excellent chance for a normal life. Modern medicine has made breathtaking advances in the survival of premature infants, and many born prematurely have improved chances of surviving and growing up to be normal, healthy children.
However, the picture is much more dismal when it comes to infants born at between 20 and 25 weeks of gestation. These are among babies considered extremely premature. A full-term pregnancy is 38 to 42 weeks of gestation; this is based on the 40 weeks between a woman's last menstrual period and her due date.
These extremely preterm babies are so early that they are often born with their eyes fused shut, their skin almost transparent, and their weight under 1.5 pounds. Most are so frail that they have difficulty just surviving labor and delivery. Often, their arms can fit through their father's wedding band.
More than three-quarters of these extremely premature babies will be stillborn or die before they ever get to the neonatal intensive care unit, and an additional 12% die before being discharged from the hospital. Of the 8% who survive long enough to leave the hospital, up to 1% will die before the age of two and a half. The small number who survive face a high risk of having some type of disability.
In a new study appearing in the current issue of The New England Journal of Medicine, nearly half of such extremely premature babies ended up with a disability. Of this group, half had a disability that was considered severe. However, the other half of those surviving to two and a half years of age had no disability.
Some of the disabilities the researchers found included:
"The take-home message from this study," says Michael Speer, MD, "is that if you're going to have a baby at 24 or 25 weeks' gestation, the risks of a significant handicap are definitely there." Speer, who was not involved in the study, is a professor of pediatrics at Baylor College of Medicine in Houston.
Led by Nicholas S. Wood, MB, ChB, of the University of Nottingham in England, the research team examined the records of all babies born between 20 and 25 completed weeks of gestation in the U.K. and Ireland during a nine-month period in 1995. Of those who survived, about 280 met the criteria for the study, and the children were assessed to see how well they were developing. This was done when the children were at a corrected age of two and a half years. The corrected age is the age the child would be if delivered on his or her due date.
Speer points out that some disabilities may lessen over time. "Some mild disability at age 2 may resolve at age 5, but a severe disability is not going to be resolved."
Learning disabilities are quite common in premature children, he adds, and some small studies have indicated that the very small premature babies may have even more learning disabilities.
The ethics of whether or not to save such a small baby, coupled with the high costs for immediate and long-term care, are two issues which remain a source of debate.
In an editorial of the study, L. Sessions Cole, MD, writes that the average cost for an infant born at less than 26 weeks' gestation who survives and who stays over four months in an intensive care unit is $250,000. He agrees that it is a lot of money to spend on a single hospitalization, but argues that cost issues need to be looked at in the full context of health care.
"The entire health care budget in the United States for children is only a small fraction of what it is for older people," he says. "I'm not denying that it's expensive, but when you look at how money is spent in other places, it's not unreasonable." Cole is a professor of pediatrics and division director of newborn medicine at Washington University School of Medicine in St. Louis.
Many people don't equate the philosophy of saving lives with the high cost, says Speer. "There's a legal precedence to protect these babies, and many of us hold the philosophical thought that everyone's life is sacred and that one should do everything in one's power to maintain that life, but they don't want to pay for it. To me that's very illogical."
At the present time, what is important for parents to understand is that there is no way of knowing which babies will do well -- and which will not. Right now, says Cole, well-informed family members who are involved with the baby's care, as well as the baby's response to treatment, are the best guideposts for making decisions about whether or not therapy is fruitless. "No parent or physician wants to give therapies to babies which are invasive, painful, and futile," he says. "But it's sometimes difficult to know, until you give the therapy, whether the baby will respond."
"The prevention or amelioration of disability in survivors of extreme prematurity," write the researchers, "remains one of the most important challenges in medicine."
However, both Cole and Speer believe that prevention of a premature birth in the first place is the most important goal, and far superior to dealing with the premature baby once it's born.
For pregnant women, that means:
The challenge for physicians, says Cole, is clear -- not to worry so much about cost issues, but instead, to try to better understand the reasons for premature birth and then prevent it.