Early neonatal mortality and cesarean delivery in Mexico City

The relationship between cesarean delivery and neonatal mortality is presented with information from 292 early neonatal deaths (cases) and 3098 survivors (controls) born in 25 hospitals in Mexico City during the summer of 1984. The overall rate of cesarean delivery was 27%. Variations between health agencies and different social groups were not related to obstetric risk, suggesting that a sizable proportion of the operations were probably unjustified. Babies of normal birth weight (greater than or equal to 2500 gm) delivered by cesarean section were 2.5 times more likely to die in the early neonatal period compared with vaginally delivered babies of the same weight. The excess of mortality could not be explained by the effect of maternal characteristics or complications or by differences in birth weight or gestational age. It is suggested that the conditions under which the operation was performed probably explain the increased risk of early neonatal death. It is likely that poor quality of resuscitation and respiratory care are implicated in the link between "unnecessary" cesarean section and early neonatal mortality.