Intrauterine growth and survival in cerebral palsy

Abstract

Background and Objectives:Deviations in birthweight from an optimum, thought to be just above average for gestational age, are known to increase both the risk of developing cerebral palsy and the risk of developing cerebral palsy of a more severe form. Influences on survival of such deviations from average birthweight for gestational age are not known.

Methods:Using a well established, well defined and large UK cohort of children and adults with cerebral palsy, followed from birth for nearly 25 years, we investigate the influence of deviations from average birthweight for gestational age, on survival duration, after allowing for severity of impairments.

Results:A total of 3946 cases, born between 1980 and 1996 were included. For those born much lighter than average for gestational age, more than 30% had a severe motor or cognitive impairment, rising to as much as 40% for extremely low weights. For females proportions severely impaired increased to as much as 35% for those born much heavier than average; no such increase was observed for heavier than average males. For those with four severe impairments and a birthweight close to average for gestational age, around 60% survived to age 15 years, compared to fewer than 40% of those born much heavier than average for gestational age. A two year old child with four severe impairments and born born heavy for gestational age has a predicted median life expectancy of 79% of the average (95% CI: 70% to 88%).

Conclusions:Infants with a birthweight lighter than average for gestational age have an increased likelihood of developing a more severe form of cerebral palsy. Surprisingly, for those who are very severely impaired, it is those born much lighter than average for gestational age who have the longest life expectancy, and those born much heavier than average for gestational age, who have the shortest life expectancy.