Tables for predicting survival for preterm births are updated

Editor—In 1999 we described mortality patterns among preterm neonates born to mothers resident in the former Trent health region.¹ The published predicted survival charts specific for birth weight and gestational age used data on all European and Asian live births, stillbirths, and late fetal losses from 22 to 32 weeks' gestation from a geographically defined population.

Such charts are believed to facilitate decision making by clinicians and parents. We acknowledge, however, that they require regular updating to allow for improvements in the survival of such infants.

The tables have now been updated using data from infants born between 1 January 1998 and 31 December 2001 to mothers resident in the then Trent health region. The data comprised 4112 births of infants known to be alive at the onset of labour. A total of 3885 infants (94.5%) were admitted to neonatal care, 3470 (89.3%) surviving to discharge home. The same statistical methods were used to produce the updated charts as described in the original paper.

These new charts can be accessed on bmj.com² They show a general increase in survival among neonates and are also believed to reflect more accurately survival among very small babies.