Trends in risk factors for caesarean sections in France between 1981 and 1995: lessons for reducing the rates in the future.

OBJECTIVE

To assess the effects of the characteristics of mothers, fetuses and maternity units on the trends in caesarean section use, especially for primiparae.

DESIGN

Cross sectional surveys.

SETTING

Maternity units.

POPULATION

Two representative national samples of births including 5410 newborns in 1981 and 13318 in 1995.

METHOD

Univariate analysis and logistic regression analysis.

RESULTS

The overall rate of caesarean section rose from 10.7% in 1981 to 15.3% in 1995. This trend is mainly attributable to the increases in the proportion of previously sectioned women (from 4.1% to 8.2%) and in caesarean sections for primiparae (from 12.6% to 17.8%). Among primiparae several maternal risk factors such as late childbearing and obesity before pregnancy were more frequent in 1995 than in 1981. The increase in caesarean sections affected both the high risk group (25.4% to 32.4%) and the low risk group (8.1% to 12.0%).

CONCLUSION

A significant reduction in the overall rate cannot be achieved without regulating caesarean section use for primiparae. Strategies to change delivery patterns should be aimed at both high and low risk women.