Drop in Delivery-Related Mortality in Term Infants Seen in Scotland

From Reuters Health Information

By Megan Rauscher

NEW YORK (Reuters Health) Aug 12 - Over the past two decades in Scotland, there was nearly a 40% decline in the risk of infants dying either during labor or shortly after birth, researchers report in the August 12th issue of the Journal of the American Medical Association.

"These pregnancies were confined to single babies, presenting head first at term and cannot, therefore, be explained by improved outcome among preterm infants or those born breech," Dr. Gordon C. S. Smith, of University of Cambridge, England, noted in an email correspondence with Reuters Health.

The decline in the rate of death was due to a reduction in the number of deaths associated with intrapartum anoxia, Dr. Smith and colleagues note in their report. There was no significant decline in other causes of death.

The findings are based on registry data for 1,012,266 single, term births in a cephalic presentation between 1988 and 2007 in Scotland. Perinatal deaths from congenital anomaly or antepartum stillbirth were excluded from the analysis.

During the study period, there were 719 delivery-related perinatal deaths (0.07%), which included 219 intrapartum stillbirths (30.5%) and 500 neonatal deaths (69.5%). Of these perinatal deaths, 432 (60.1%) were caused by intrapartum anoxia and 287 (39.9%) were due to other causes.

The absolute risk of delivery-related perinatal death in the population was 7.1 per 10,000 births, the investigators report.

During the study period, the risk of delivery-related perinatal death declined from 8.8 to 5.5 per 10,000 births - a decrease of 38%. When analyzed by cause of death, the risk of death due to intrapartum anoxia fell 47% from 5.7 to 3.0 per 10,000 births, while no significant change occurred in the risk of death due to other causes.

"There did not appear to be any change in maternal characteristics that explained the decline," Dr. Smith told Reuters Health. "It was independent of changes in maternal age, parity and height. There was, however, a parallel increase in the rate of cesarean section over the study period."

However, there was no direct evidence indicating that the decline in death rate was explained by rising cesarean section rates. "There was a negative association between the rate of death and the rate of cesarean section, but it is impossible to infer whether this was cause and effect," Dr. Smith commented.

JAMA 2009;302:660-668.

Reuters Health Information © 2009