Low birthweight linked to higher death rates in infants and adolescents

Babies born with a low birthweight are at an increased risk of death in infancy right through to adolescence compared to babies born at a normal birthweight, according to new research.

A team from Cardiff University's School of Medicine, led by Professor Sailesh Kotecha, examined official death rates in low birthweight babies among over 12m births in England and Wales.

The research, published in the journal PLOS Medicine, found that of the 12,355,251 live births between 1993 and 2011, there were 74,890 (0.61%) deaths between birth and 18 years of age, with 57,623 (77%) occurring in the first year of life and 17,267 (23%) occurring between 1 and 18 years of age.

Death rates were higher in babies with low birthweight at both age groups, with death occurring 130 times more frequently in those born at a very low birthweight (under 2,500g) than normal birth weight in infancy.

Events occurring around birth and premature births were important causes of deaths in infancy.

Causes for deaths in those aged 1 and 18 years of age were more evenly distributed across causes, with conditions of the nervous system (20%) and respiratory system (16%) being leading causes of death in the lowest birthweight group but cancers and external conditions (including accidents) being the primary causes of death in low birthweight groups.

Professor Kotecha said: "We know low birthweight is associated with increased mortality rates in infancy; however, its association with mortality in later childhood and adolescence is less clear cut.

"This study is significant as it shows, for the first time, that low birthweight is associated with increased death rates from infancy right through to adolescence."

As the team point out, the study was observational however they believe it reinforces the need to target factors known to contribute to low birthweights to help cut deaths.

Professor Kotecha added: "The study reaffirms the need to tackle important factors such as maternal smoking and deprivation which are well known to contribute to low birth weight.

"By better understanding and ameliorating influences that lead to low birthweight, deaths in infancy and beyond could be cut."