Lowering the cesarean section rate in a private hospital: comparison of individual physicians' rates, risk factors, and outcomes

OBJECTIVE

Our purpose was to compare the practice patterns and outcomes of physicians delivering in our institution to identify risk factors and management techniques that could explain the differences in individual cesarean section rates.

STUDY DESIGN

We retrospectively reviewed detailed computerized delivery records (n = 16,230) collected from May 16, 1988, to July 30, 1995. We excluded physicians who had <100 deliveries at our institution during the study period. The physicians were divided into two groups depending on whether their individual cesarean section rates were greater than (control group) or less than 15% (target group). Various cesarean section rates, risk factors for abdominal delivery, labor management techniques, and neonatal outcome parameters were calculated for each group. The cesarean section rates of the two groups were analyzed by year to assess changes.

RESULTS

As expected by study design, the overall cesarean section rate was markedly different between the two groups (13.8% vs 23.8%). In addition, the primary, repeat, primigravid, and multiparous cesarean section rates were all lower for the target group. The rates of cesarean section for fetal distress (1.5% vs 3.3%) and cephalopelvic disproportion (5.3% vs 8.5%) were also significantly less in the target group. The rates of breech presentation, third-trimester bleeding, and active herpes cesarean sections were not lower. The control group had more postterm (8.6% vs 14.7%) and >4000 gm infants (12.0% vs 13.7%) but similar numbers of low birth weight, multiple gestation, and preterm infants. The target group used more epidural anesthesia, oxytocin induction, and trial vaginal births after cesarean delivery and more successful trial vaginal births after cesarean sections. Over the study period the cesarean section rate in the target group remained unchanged, whereas it steadily declined in the control group.

CONCLUSIONS

Individual physician's lower cesarean sections are primarily obtained by labor management and attempting vaginal birth after cesarean delivery. These practice patterns did not appear to lead to any increase in perinatal morbidity or mortality. Efforts to lower cesarean section rates of individual practitioners should focus on the areas of fetal distress, cephalopelvic disproportion, and repeat cesarean section.

Prolonged bedrest during pregnancy: does the risk of deep vein thrombosis warrant the use of routine heparin prophylaxis?

This is the first study to assess the risk of clinically apparent DVT in pregnant women placed in the hospital at prolonged bedrest. The outcome is discussed with reference to the risks associated with heparin. Information, including delivery data, length of hospital stay, and discharge diagnoses were extracted from a prospectively collected computerized data bank of all deliveries that occurred over a 5.5-year period at Long Beach Memorial Women's Hospital in Long Beach, California, and at St. Joseph's Hospital in Milwaukee, Wisconsin. One group consisted of all pregnant women who had been hospitalized at prolonged antepartum bedrest, as defined by 3 weeks or more. The other group consisted of the remaining population of women whose deliveries occurred during the same time period. There were 48,525 deliveries during the study period, and 266 (0.5%) women were hospitalized at prolonged antepartum bedrest. The mean number of days in the hospital for these women was 34.6 +/- 14 (range 21-82 days). Of these women, one received prophylactic heparin for a prior history of DVT. There were no cases of DVT in the 265 women who did not receive heparin, risk = 0.0 (CI = 0.00-0.99). Of these 265 women, 234 were hospitalized up to the day of delivery. Of these 234 women, 154 (65.8%) underwent cesarean section and no case of DVT occurred in the postoperative period, risk = 0.0 (CI = 0.0-1.7). Out of the remaining 48,259 women who were not hospitalized at prolonged bedrest, there were 18 cases of clinically apparent DVT, and the longest antepartum hospitalization was 4 days. A conservative risk of complications with prophylactic heparin therapy is 1.0% or greater. Although the risk of DVT in pregnant women hospitalized at prolonged bedrest is not zero, our study indicates that it is very low (< 1.0%). Whereas a risk of DVT of at least 1.0% could warrant heparin prophylaxis, even with 265 patients at prolonged bedrest and 48,525 controls, this risk could not be demonstrated. Using a power analysis with an alpha of 0.05 and a power of 80% to demonstrate this risk, one would need 247 cases and approximately 49,000 controls, which were clearly achieved in this study. In view of the risks associated with heparin, routine antenatal prophylaxis is not recommended unless other risk factors for DVT are present.

Factors contributing to the increased cesarean birth rate in older parturient women

OBJECTIVE

Our purpose was to determine factors contributing to the increased use of cesarean section in patients > or = 35 years old.

STUDY DESIGN

Data were collected prospectively on nulliparous patients in spontaneous labor with term, singleton pregnancies and vertex presentations. Criteria for the diagnosis of labor were standardized: regular, painful uterine contractions at least once every 5 minutes in the presence of either complete cervical effacement or spontaneous rupture of membranes. The labors of women > or = 35 years old (n = 74) were compared with those of women 20 to 29 years old (n = 275).

RESULTS

The cesarean section rate was significantly greater for patients > or = 35 years old (21.6% vs 10.2%, odds ratio 2.4, 95% confidence interval 1.2 to 5.1). Mean birth weights were similar in the two groups, but when birth weight was > or = 3600 gm patients > or = 35 years old were more likely to be delivered by cesarean section (36.7% vs 12.2%, odds ratio 4.0, 95% confidence interval 1.4 to 11.9). There were no differences between the two age groups in physician factors that could explain the disparate rates of cesarean delivery. Indeed, of patients delivered vaginally the older parturients received oxytocin for longer duration (6.4 +/- 2.6 vs 5.0 +/- 3.1 hours, p < 0.05) and at higher maximum doses (12.4 +/- 6.1 vs 9.8 +/- 6.2 mU, p < 0.05). After controlling for potentially confounding variables with multiple logistic regression analysis, maternal age (R = 0.125, p < 0.005), birth weight (R = 0.196, p < 0.001), the need for oxytocin (R = 0.210, p < 0.001), and epidural anesthesia (R = 0.195, p < 0.001) were found to be independently associated with the increased rate of cesarean section.

CONCLUSION

We could not identify any controllable physician factors affecting the rate of cesarean section in patients > or = 35 years old. The increased oxytocin requirements and the incidence of dystocia with birth weight > or = 3600 gm suggest that maternal and fetal characteristics contribute to the increased frequency of cesarean section in older parturients.

A controlled trial of a program for the active management of labor

BACKGROUND

Over the past two decades, the rate of cesarean section in the United States has risen from 5 percent to 25 percent of deliveries, primarily because of the increased frequency of dystocia (arrest of labor). One strategy that has been proposed for increasing the rate of vaginal delivery is a program of active management of labor that encourages early amniotomy, early diagnosis of slow progress in labor, and the use of higher than usual doses of oxytocin; the efficacy and safety of this approach are uncertain, however.

METHODS

We conducted a randomized trial in which nulliparous women in spontaneous labor at term were randomly assigned to either active management of labor or traditional management. With active management, amniotomy was performed within one hour of the diagnosis of labor, and when the rate of cervical dilation was less than 1 cm per hour, oxytocin was infused at an initial rate of 6 mU per minute. The dose was increased by 6 mU per minute every 15 minutes (to a maximum of 36 mU per minute) until there were seven contractions every 15 minutes.

RESULTS

For the women assigned to active management (n = 351), the cesarean-section rate was 10.5 percent, as compared with 14.1 percent for those assigned to traditional management (n = 354, P = 0.18). The 26 percent reduction in the cesarean-section rate was due primarily to a decrease in dystocia. After we controlled for potential confounding variables, the reduction in the rate of delivery by cesarean section was statistically significant (odds ratio for women given active as compared with traditional management, 0.57; 95 percent confidence interval, 0.36 to 0.95). With active management, the average length of labor was shortened by 1.66 hours, principally because of earlier amniotomy and earlier use of oxytocin. There was no increase in maternal or neonatal morbidity, and there were significantly fewer infectious complications in the mothers.

CONCLUSIONS

The program we studied for the active management of labor reduces the incidence of dystocia and increases the rate of vaginal delivery without increasing maternal or neonatal morbidity.