Ottawa study looks at preemies
An Ottawa survey of 738 premature infants, published Monday, offers new guidance for parents. JOANNE LAUCIUS reports.
Gabriel Amador was born threeand-a-half years ago, so tiny he was weighed in grams — 515 grams, or one pound, two ounces. So tiny he could wear his parents’ wedding rings on his upper arms.
Three-and-a-half years later, Gabriel has ADHD and global developmental delay, with delayed cognitive functioning and gross and delayed gross and fine motor delay. His speech is limited to about 20 words, but he can walk and run.
“We had so many professionals tell us that he might have cerebral palsy, that he might be blind, or have hearing problems or spina bifida,” says Gabriel’s mother, Amanda Cooke.
Babies like Gabriel, born at 22 to 26 weeks’ gestation, are considered to be “on the edge of viability.”
Some don’t survive — according to the Canadian Neonatal Network’s 2011 report, fewer than 30 per cent of babies born at less than 23 weeks’ gestation who were admitted to neonatal intensive care units survive.
The survival rates climb as the weeks go by. At 25 weeks, it’s almost 80 per cent.
The parents of babies born extremely prematurely often have a hard choice to make. They can choose intensive care for their tiny infant, or palliative care. For many, the chance of the baby’s surviving with long-term neurological impairment, such as cerebral palsy and the inability to walk, is the deciding factor.
Parents want to know what to expect. But doctors haven’t been able to give them good answers, says Dr. Gregory Moore, a neonatologist at the Ottawa Hospital and CHEO and an assistant professor at the University of Ottawa.
There are a lot of numbers about the survival of extreme pre-term babies, but little that looks down the road to see how they are doing once they reach school age.
Moore and a team of Ottawa neonatologists and a statistician looked at the outcomes in nine international studies in the hopes that their findings will help guide parents. Their study is the first strict meta-analysis — a pooling of data from numerous sources — on the subject. It was published Monday by the Journal of the American Medical Association Pediatrics.
The researchers hunted down studies involving 738 extremely pre-term infants born in Europe, the United Kingdom, Australia and New Zealand. All of the babies in the studies had been born between 22 weeks and 25 weeks plus six days of gestation.
The data included birth records of the babies as well as cognitive testing done four to eight years later to find out how these children were progressing in key areas of neurodevelopment, including visual and hearing impairment and cerebral palsy.
Infants born at term have a four per cent chance of a neuro-developmental impairment, but the risk for extremely pre-term babies is much more significant.
The Ottawa researchers found that between 14 and 31 per cent of the infants born between 22 and 25 weeks’ gestation had severe developmental problems at the age of four to eight, with at least one of the following: an IQ more than three standard deviations below the mean, cerebral palsy without the ability to walk independently, no useful vision, or no useful hearing.
Whether the babies were born at 22, 23, 24 or 25 weeks gestation, there was no statistically-significant difference in the proportion with severe developmental problems.
However, when “moderate” problems were considered, there was a six per cent decrease in developmental problems with every extra week of gestation.
Overall, the data will give parents a much better picture of what to expect, and it will help them make decisions with their doctors about the care for their baby.
In a position statement released last October, the Canadian Paediatric Society pointed out that parental concerns about quality of life, neurodevelopment and increased health costs are complex and controversial, and there is no universal agreement on how to approach and manage these decisions.
Cooke was pregnant only 25 weeks when a healthy pregnancy, her second, came screeching to a halt. Her liver was failing and her blood pressure was escalating. She was given two steroid injections to prevent her baby from being born. Every day increased his chance of survival.
Two days later, Cooke went into labour. Asked whether they wanted resuscitation for their baby, Cooke and her husband, Rodrigo Amador, said they did.
Cooke says she and Amador are spiritual, but not religious. “I made a deal with God,” she says. “If there was a chance, I promised to handle whatever was thrown our way.”
Every baby is different, and it’s impossible to predict what will happen, says Moore. There is a very good chance there might not be any impairment.
“The really important thing is that these limitations have to be discussed,” he says.
Cooke does not regret her choice. Gabriel is loving and he has a lot of determination, she says.
“Every day is a struggle. But he has taught us a lot.”