Cesarean sections in upstate New York, 1968-1978.

Data from birth certificates were used to examine the changing trends in the use of cesarean section from 1968 to 1978 in upstate New York. Differences in the percentages of primary cesarean section among population subgroups are cited. Hospital-to-hospital variation in the use of primary cesarean section is shown, as is the relationship among per cent primary cesarean section, hospital size, neonatal mortality, and the per cent of breech deliveries. The percentage of births delivered via cesarean section in 1978 is four times the percentage of 1968 (from 2.5-10.2% for whites, from 3.1-11.5% for nonwhites). Among the subgroups of the population, the increase has ranged from one and one-half to five times the 1968 percentage. There was little hospital-to-hospital variation in the percentage of primary cesarean section in 1968-1969; however, in 1977-1978 the per cent of deliveries performed by primary cesarean section varied from 1-22%. While neonatal mortality was found to be related to the percentage of cesarean section performed in hospitals in 1968-1969, no such association was found in 1977-1978. An inverse relationship was found between the percentage of breech deliveries and the percentage of cesarean sections performed in hospitals in 1977-1978.