Reasons for the rising cesarean delivery rates: 1978-1984.

This study was undertaken to estimate the cesarean delivery rate in United States hospitals and to determine whether the reasons for rise in this rate have changed since the National Institute of Child Health and Human Development Consensus Development Conference on Cesarean Childbirth in 1979. The cesarean delivery rate steadily increased from 9.1% in 1974 to 14.7% in 1978, and to 21.2% in 1984. One-third of the rise in the cesarean rate from 1974-1978 was due to repeat cesareans, and 9% was due to fetal distress. Since 1978, 47% of the rise in the cesarean rate was attributed to repeat cesareans, and 16% to fetal distress. Less of the recent rise in the cesarean rate was due to dystocia and breech presentation. The rate of cesarean delivery among those with a previous cesarean was 96%. Deliveries complicated by fetal distress increased from 1% in 1978 to 6% in 1984. The incidence of breech presentation dropped by 18% (2.8-2.3%), which may indicate an increase in the successful use of external cephalic version. If the number of vaginal deliveries after cesarean increases in the future, then the overall cesarean delivery rate will decrease or stabilize. Additional efforts should be focused on the diagnostic categories of fetal distress and dystocia, because it is likely that the definitions of these complications are changing to include less severe forms.