Advances in medical technology have allowed extremely premature, featherweight babies to survive, but there has long been a grim assumption they will suffer lifelong physical disabilities and mental impairments.
Now, a new Canadian study is challenging that assumption, showing that many superpreemies who survive the precarious first months of life tend to do as well as normal birth-weight babies in terms of education, employment and independence.
"Our study should provide hope to parents for an equivalent, if not better, future for their premature children," said Dr. Saroj Saigal, a researcher in the department of pediatrics at McMaster University in Hamilton, Ont.
The study, published in today's edition of the Journal of the American Medical Association, is one of the first to follow a large group of very premature babies from birth through to adulthood. The study participants are the first generation to benefit from dramatic advances in neonatology in the early 1980s.
Rishi Kapur, who was born at McMaster Hospital in 1980, is typical of that group. He was born at 28 weeks gestation, weighing only 850 grams (one pound, 14 ounces), tiny enough to fit in the palm of his mother's hand. (A full gestation is 40 weeks, and a normal birth weight is about 3,500 grams (seven pounds, 11 ounces).
"I was lucky because there was a big jump in technology just before I was born," Mr. Kapur said. "A few years earlier, and it would have been much more risky -- I probably wouldn't have made it."
Despite his precarious beginnings, Mr. Kapur defies the stereotype of the superpreemie. He has no major health problems or mental impairments. In fact, the 25-year-old has excelled and is a medical student at the University of Toronto.
The new study shows that the majority of superpreemies "made a successful transition to adulthood" -- meaning their education, employment, marriage and parenthood levels were similar to those of normal birth-weight babies.
Researchers followed 149 extremely low birth-weight babies, born from 1977 to 1982, to the present, and compared them to a demographically similar group of 133 normal birth-weight babies. The superpreemies weighed, on average, 841 grams and were born at 27 weeks; the regular-weight babies weighed an average 3,384 grams at 40 weeks gestation.
Dr. Saigal noted, however, that those studied were the survivors -- a striking 55 per cent of superpreemies died in hospital in their first months. And one in four of the extremely low birth-weight babies (ELBW) who survived to adulthood had "neurosensory impairments," such as cerebral palsy, autism and blindness.
Still, Dr. Saigal said the research findings challenge predictions that most superpreemies would never become fully independent adults. "Against our expectations and many odds, a significant majority of ELBW young adults have overcome early difficulties to become functional members of society," she said, a testament to the "remarkable resilience" of the superpreemies.
The study showed 82 per cent of ELBW babies graduated from high school, compared with 87 per cent of normal birth-weight babies; 32 per cent versus 33 per cent were still pursuing postsecondary education; 48 per cent versus 57 per cent were permanently employed. The number of ELBW babies and normal birth-weight babies who had grown up to live independently in young adulthood was comparable at 42 per cent versus 53 per cent; marriage rates were similar, 23 per cent versus 25 per cent; and so, too, were the rates of parenthood, 11 per cent versus 14 per cent.
The only area where significant differences surfaced is when researchers compared those in both groups who were neither employed nor in school -- 26 per cent of ELBW babies versus 15 per cent of normal birth-weight infants. But Dr. Saigal found that once ELBW babies with severe disabilities were excluded, that number was comparable, too.
In an editorial also published in JAMA, Maureen Hack, of Rainbow Babies and Children's Hospital and Case Western Reserve University in Cleveland, said the research findings are enlightening but warned that they are not necessarily applicable to superpreemies born today.
She said technological and therapeutic advances in neonatal intensive care over the past two decades have hiked the survival rate to almost 80 per cent, but children are now surviving with far more severe disabilities.