Indications contributing to the increasing cesarean delivery rate

Abstract

Objective: To examine physician-documented indications for cesarean delivery in order to investigate the specific factors contributing to the increasing cesarean delivery rate.

Methods: We analyzed rates of primary and repeat cesarean delivery, including indications for the procedure, among 32,443 live births at a major academic hospital between 2003 and 2009. Time trends for each indication were modeled to estimate the absolute and cumulative annualized relative risk of cesarean by indication over time and the relative contribution of each indication to the overall increase in primary cesarean delivery rate.

Results: The cesarean delivery rate increased from 26% to 36.5% between 2003 and 2009; 50.0% of the increase was attributable to an increase in primary cesarean delivery. Among the documented indications, nonreassuring fetal status, arrest of dilation, multiple gestation, preeclampsia, suspected macrosomia, and maternal request increased over time, whereas arrest of descent, malpresentation, maternal-fetal indications, and other obstetric indications (eg, cord prolapse, placenta previa) did not increase. The relative contributions of each indication to the total increase in primary cesarean rate were: nonreassuring fetal status (32%), labor arrest disorders (18%), multiple gestation (16%), suspected macrosomia (10%), preeclampsia (10%), maternal request (8%), maternal-fetal conditions (5%), and other obstetric conditions (1%).

Conclusion: Primary cesarean births accounted for 50% of the increasing cesarean rate. Among primary cesarean deliveries, more subjective indications (nonreassuring fetal status and arrest of dilation) contributed larger proportions than more objective indications (malpresentation, maternal-fetal, and obstetric conditions).

Conflict of interest statement

Financial Disclosure: The authors did not report any potential conflicts of interest.

Figures

Figure 1

Cesarean delivery rates (%) were calculated for each year from 1996 to 2009. Cesarean rates represent number of cesarean births divided by total live births.

Figure 2

The vaginal birth after cesarean delivery (VBAC) rate was calculated for each year from 1996 to 2009. VBAC rate represents number of successful VBACs divided by the number of women who underwent previous cesarean delivery.

Figure 3

Cesarean delivery rate (%) by provider category. Cesarean delivery rates were calculated for patients cared for by the high risk, private, and university services. Cesarean rates represent number of cesarean deliveries in each category divided by number of live births in each provider category.

Figure 4

The number of cesarean deliveries performed for each indication per 1,000 women at risk for primary cesarean delivery. A. Primary cesarean deliveries grouped by indication. Each vertical bar represents the total number of primary cesareans performed each year per 1,000 eligible live births, and the divisions within each bar represent the number of cesareans performed for each indication. The purple bar represents an “other” category made up of 6 indications which are delineated further in Figure 4b. B: Primary cesarean deliveries grouped by indication. A smaller scale is provided to allow for a clearer view of how the six indications that make up the “other” category in Figure 4a changed over the 6-year period. *Eligible live births were births to women with no prior history of cesarean delivery.

Figure 5

Contribution of each indication to the total increase in primary cesarean deliveries. The proportions each indication contributed to the overall increase in primary cesarean delivery from 2003 to 2009 are graphed in comparison to one another.