Premmie babies: our tiny problem, growing bigger
Premature babies are on the increase in Australia. Timothy Moss, senior research fellow at the Ritchie Centre, Monash Institute of Medical Research, examines the difficult conundrum.
There's an international awareness day for just about everything these days, so it's not surprising that World Prematurity Day came and went on November 17 without anyone noticing.
The little international media coverage received focused on the devastating impact of preterm birth in low-income countries. However, it also raises significant medical -- and ethical -- issues in Australia, where over 8% of babies -- almost 30,000 a year -- are born preterm (before 37 completed weeks of gestation; full term is 40 weeks).
This rate has risen from around 7% a decade ago. At the same time the number of babies born nationally has increased overall, making premature babies a growing problem.
There is no way to predict or prevent the vast majority of preterm births, so we are left, quite literally, holding the baby.
Modern care of pregnant women and their babies provides high rates of survival in high-income countries like Australia, even for babies born very early. Fifty percent of premature babies born at 24-25 weeks of gestation, and over 90% of those born at 28 weeks, now survive.
However, extremely preterm babies born at the threshold of viability (less than 26 weeks gestation) present a particularly difficult challenge: how do we ensure survival without disability?
The immaturity of extremely premature babies results in devastating consequences. Brain injury and difficulties with breathing can require months in a special care nursery and cause life-long neurological disability, ranging from learning disabilities to severe impairments like cerebral palsy, blindness and deafness. Long-term survival without some form of severe neurological disability is achieved only for only about half of these babies.
Increasingly, neonatal intensive case units (NICUs) and special care nurseries are looking after tiny patients with uncertain prospects for the future. There are no universal guidelines to direct doctors' management of extremely premature infants. In Singapore and The Netherlands, for example, guidelines suggest provision of lifesaving care only to infants born after 25 weeks. In Australia, how a preterm baby is managed -- i.e. whether to pursue certain treatments or not -- varies between individual doctors, hospitals and states.
Decisions about care are "strongly influenced" by a doctor's own personal medical experience with extremely preterm infants, according to Prof Jane Pillow, a neonatologist at Perth's King Edward Memorial Hospital, home of the largest NICU in the country.
"In Western Australia, babies tend to have improved outcomes compared with internationally published figures," Pillow told Crikey. "Our success therefore influences our preparedness to actively resuscitate and care for the infants."
But sometimes tough choices must be made. "The decision to resuscitate or not should be individualised to the clinical scenario, and must involve close consultation and active, fully informed input from the family," Pillow said. "We would normally indicate to parents that if outcome is looking poor then withdrawal of intensive care remains an option."
The full extent of the consequences of extremely preterm birth are unknown because survival of these babies is only a recent phenomenon. Most survivors are not old enough for us to know the true long-term consequences. The limited information from adult survivors shows lower educational achievement and ongoing health problems.
At the other end of the scale, late preterm births (between 34 and 36 weeks of gestation) pose a different problem.
Even these babies, born close to full term, are at risk. Late preterm infants constitute more than half of premature births and the majority of the increase in the overall preterm birth rate over recent years. An increase in older mothers, the use of assisted reproductive techniques like IVF and high rates of elective delivery (i.e. caesareans or induction of labour) also contribute.
Late preterm babies are far less imperiled than those born just a few weeks earlier, but they are still five times more likely to die than babies born at term. According to a recent review of the scientific literature by Professor Lex Doyle's group at Melbourne's Royal Women's Hospital, these babies have higher-than-normal rates of a variety of illnesses while in hospital. Perhaps even more concerning, late preterm babies are more likely to experience learning and physical disabilities later in life, and are 40% more likely to suffer a major psychiatric disorders (such as schizophrenia) as young adults.
This problem will increase "because they are the babies whose birth rate is increasing most rapidly," Doyle told Crikey.
As dire as these consequences of preterm birth seem, the scale of the problem in Australia is dwarfed by its impact in low-income countries. Fifteen million premature babies will be born worldwide this year, 60% of these in southern Asia and sub-Saharan Africa. One million of them will die.
In low-income countries, only 10% of babies born before 28 weeks of gestation survive. It is not until 32 weeks that 50% survival is achieved.
There are a few simple, inexpensive things that can be done to improve these babies' survival rate. Providing steroid injections to women at risk of premature birth (routine in developed countries) could prevent over 370,000 deaths annually. Reducing maternal smoking could significantly reduce preterm birth rates. Supporting breastfeeding and encouraging "kangaroo care", skin-to-skin contact between mother and baby, could save thousands of lives.
Preterm birth is the second-greatest cause of death of children under five worldwide (pneumonia is first). If the United Nations' Millennium Development Goal to "reduce by two thirds, between 1990 and 2015, the under-five mortality rate" is going to be met, simple measures to prevent preterm birth in the developing world must be implemented immediately.
In Australia, the "vast majority" of our extremely premature babies end up "making good progress through their childhood years, look to have reasonable prospects of living independently in the future, love being who they are and are a source of joy to their family," says Pillow. This seems like a reasonable aspiration for all preterm babies.
Moss is currently interning at Crikey as part of the Australia Science Media Centre's internship program.