Trends in maternal request cesarean delivery from 1991 to 2004.

OBJECTIVE: To review definitions and terminology for and to estimate percentages of maternal request cesarean deliveries in the United States between 1991 and 2004.
METHODS: National Hospital Discharge Survey data 1991-2004 (N=458,767) were used to identify maternal request cesarean deliveries. After excluding women with a history of cesarean delivery, women who labored, and women with indicated risks against labor, 2,394 potential maternal request cesarean deliveries remained. Indicated risks were identified with a recognized protocol.
RESULTS: Maternal request cesarean deliveries have two properties: 1) cesarean delivery before labor and 2) cesarean delivery in the absence of medical conditions presenting a risk for labor. Risk is either absolutely absent or it is relatively absent. In 1991-2004, 0.20% of women who delivered live infants and 1.34% of women who delivered by primary cesarean delivery did so without any medical conditions listed on their hospital discharge record. Estimates for maternal request cesarean deliveries without certain indicated risks were 0.75% for women who delivered live infants and 5.03% for women who delivered by primary cesarean delivery. Maternal request cesarean deliveries without any indicated risk peaked in 1999 for women who delivered live infants. Maternal request cesarean deliveries without certain indicated risks crested in 2004.
CONCLUSION: Our estimates were affected by three factors: 1) lack of agreement on a definition of maternal request cesarean deliveries, 2) changes in medical coding practices, and 3) changes in physician response to medical conditions. To validly and reliably estimate maternal request cesarean deliveries requires an empirically tractable, standard definition. LEVEL OF EVIDENCE: III.