Higher Risk Of Cesarean Delivery Research Articles

Assessing the Role of Case Mix in Cesarean Delivery Rates

Objective: Implicit in comparisons of unadjusted cesarean rates for hospitals and providers is the assumption that differences result from management practices rather than differences in case mix. This study proposes a method for comparison of cesarean rates that takes the effect of case mix into account. Methods: All women delivered of infants at our institution from December 1, 1994, through July 31, 1995, were classified according to whether they received care from community-based practitioners ( N = 3913) or from the hospital-based practice that serves a higher-risk population ( N = 1556). Women were categorized according to both obstetric history (nulliparas, multiparas without a previous cesarean, multiparas with a previous cesarean) and the presence of obstetric conditions influencing the risk of cesarean delivery (multiple birth, breech presentation or transverse lie, preterm, no trial of labor for a medical indication). We determined the percent of women in each parity–obstetric condition subgroup and calculated a standardized cesarean rate for the hospital-based practice using the case mix of the community-based practitioners as the standard. Results: The crude cesarean rate was higher for the hospital-based practice (24.4%) than for the community-based practitioners (21.5%), a rate difference of 2.9% (95% confidence interval = 0.4%, 5.4%; P = .02). However, the proportion of women falling into categories conferring a high risk of cesarean delivery (multiple pregnancy, breech presentation or transverse lie, preterm, no trial of labor permitted) was twice as high for the hospital-based practice (24.4% hospital, 12.1% community). The standardization indicates that if the hospital-based practitioners had the same case mix as community-based practitioners, their overall cesarean rate would be 20.1%, similar to the 21.5% rate of community providers (rate difference = −1.4%, 95% confidence interval = −3.1%, 0.3%; P = .11). Conclusion: Standardization for case mix provides a mechanism for distinguishing differences in cesarean rates resulting from case mix from those relating to differences in practice. The methodology is not complex and could be applied to facilitate fairer comparisons of rates among providers and across institutions.

A Randomized Trial of Misoprostol and Extra-amniotic Saline Infusion for Cervical Ripening and Labor Induction

Objective: To compare the cesarean rates in women undergoing induction of labor with unfavorable cervices who receive either misoprostol or extra-amniotic saline infusion. Methods: We assigned 250 women undergoing indicated induction of labor randomly to misoprostol (50 μg every 4 hours for three doses with or without oxytocin) or extra-amniotic saline infusion and oxytocin. Each eligible subject had a singleton gestation, vertex presentation, intact membranes, cervical dilation no more than 2 cm, and effacement no more than 50%. Results: Two hundred forty-eight women were studied after two exclusions; 120 were assigned to misoprostol, and 128 to extra-amniotic saline infusion. This sample size ensured an 80% chance of detecting an intergroup difference in cesarean rates of at least two-fold. The groups were similar in age, race, parity, indication for induction, and gestational age. The extra-amniotic saline infusion group had a significantly lower median initial dilation; however, at 12 hours, this group was significantly more dilated. The groups also were similar in epidural use, chorioamnionitis rates, endometritis rates, birth weights, and neonatal outcomes. Overall, 23% of women underwent cesarean deliveries, 18% and 27% for the misoprostol and extra-amniotic saline infusion groups, respectively ( P = .12). There were no significant differences in the median time to either vaginal or cesarean delivery between the two groups. Eighty-one percent of women were delivered in less than 24 hours from initiation of induction; 78% in the misoprostol group, and 84% in the extra-amniotic saline infusion group ( P = .19). Conclusion: Both methods of labor induction appear to be equally effective in this group of women at high risk for cesarean delivery and prolonged induction of labor.

A Randomized Trial of Misoprostol and Extra-amniotic Saline Infusion for Cervical Ripening and Labor Induction

In Brief Objective To compare the cesarean rates in women undergoing induction of labor with unfavorable cervices who receive either misoprostol or extra-amniotic saline infusion. Methods We assigned 250 women undergoing indicated induction of labor randomly to misoprostol (50 μg every 4 hours for three doses with or without oxytocin) or extra-amniotic saline infusion and oxytocin. Each eligible subject had a singleton gestation, vertex presentation, intact membranes, cervical dilation no more than 2 cm, and effacement no more than 50%. Results Two hundred forty-eight women were studied after two exclusions; 120 were assigned to misoprostol, and 128 to extra-amniotic saline infusion. This sample size ensured an 80% chance of detecting an intergroup difference in cesarean rates of at least two-fold. The groups were similar in age, race, parity, indication for induction, and gestational age. The extra-amniotic saline infusion group had a significantly lower median initial dilation; however, at 12 hours, this group was significantly more dilated. The groups also were similar in epidural use, chorioamnionitis rates, endometritis rates, birth weights, and neonatal outcomes. Overall, 23% of women underwent cesarean deliveries, 18% and 27% for the misoprostol and extra-amniotic saline infusion groups, respectively (P = .12). There were no significant differences in the median time to either vaginal or cesarean delivery between the two groups. Eighty-one percent of women were delivered in less than 24 hours from initiation of induction; 78% in the misoprostol group, and 84% in the extra-amniotic saline infusion group (P = .19). Conclusion Both methods of labor induction appear to be equally effective in this group of women at high risk for cesarean delivery and prolonged induction of labor. Misoprostol and extra-amniotic saline infusion appear to be equally effective for cervical ripening and labor induction in women with unfavorable cervices.

The labor-adjusted cesarean section rate—A more informative method than the cesarean section “rate” for assessing a practitioner's labor and delivery skills

OBJECTIVE: Our purpose was to determine the benefits of an acuity-adjusted labor management tool. STUDY DESIGN: A retrospective review was performed of all deliveries at Good Samaritan Regional Medical Center in Phoenix, Arizona, for a 1-year period from Jan. 1 to Dec. 31, 1994. All physicians with ≥20 deliveries were included in the analysis. Patients with indications for which most practitioners would perform a cesarean delivery were removed from consideration. Physicians were then compared with respect to labor management in the remaining patients without relative contraindications to vaginal delivery. RESULTS: The total number of deliveries (n = 6062) was performed by 47 attending obstetricians, 9 perinatologists, an obstetrics-gynecology clinic, and a family practice clinic. The “raw” cesarean section rate was 20.1%. Those at high risk for cesarean delivery (n = 534) were excluded, leaving 684 cesarean sections performed in 5528 patients (12.4%) who were appropriate to labor. Differences were observed between the nulliparous cesarean section rate (16%) compared with that for parous patients (10.1%) (p < 0.0001 by Fisher's exact test (two-tailed) but not between attending obstetrician-gynecologists (12.4%) and perinatologists (13.8%) (not significant). CONCLUSION: A labor-adjusted cesarean section rate is more appropriate than just “raw” data. Medical, obstetric, and fetal factors affect a “raw” rate that is out of the control of the obstetrician. This method of assessing the labor and delivery skills of each practitioner and hospital would allow meaningful comparison with others. (Am J Obstet Gynecol 1997;177:139-43)

Preeclampsia, labor duration and mode of delivery

Objective: To determine if there is a difference in the length of labor, and method of delivery between preeclamptic and normotensive patients. Methods: A retrospective case control study was performed using a perinatal database. Study subjects included nulliparous patients diagnosed with preeclampsia, and were compared with normotensive nulliparous patients. Results: There were 1454 controls and 727 subjects identified. There was no difference between groups with regard to duration of total labor. There was a statistically but not clinically significant increase in the duration of the second stage in preeclamptics (35 vs. 27 min, P = 0.003). Preeclamptics had a consistently higher risk of cesarean delivery, even when controlled for confounding variables. Conclusion: The clinical belief that preeclamptic patients have more rapid labors is not supported. Preeclamptics do seem to have a higher risk of cesarean delivery.

Preeclampsia: Is induction of labor more successful?

To test the hypothesis that preeclamptic women are more readily inducible than are nonpreeclamptic women, regardless of cervical condition. One hundred eighty-three preeclamptic women and 461 nonpreeclamptic women requiring labor induction were studied prospectively. Patients were categorized by Bishop score, parity, gestational age, and method of induction. Outcome variables were success of induction and cesarean delivery rates. Failed induction was significantly more common in the preeclamptic group (8.2% versus 1.7%; odds ratio [OR] 5.06; 95% confidence interval [CI] 1.97, 13.28), as was cesarean delivery (28% versus 16%; OR 2.09; 95% CI 1.36, 3.18). When controlled by logistic regression for Bishop score, parity, method of induction, epidural anesthesia, macrosomia, and gestational age, a fourfold higher risk of failed induction and a twofold higher risk of cesarean delivery were found in the preeclamptic group. Induction of labor in preeclamptic women has a higher risk of failure and consequently of cesarean delivery than in nonpreeclamptic women. The vast majority of patients achieve vaginal delivery.

Factors relevant to mode of preterm delivery with syndrome of HELLP (hemolysis, elevated liver enzymes, and low platelets)

OBJECTIVE: Our purpose was to investigate factors relevant to mode of delivery for patients with preterm (<34 weeks) gestation complicated by the syndrome of hemolysis, elevated liver enzymes, and low platelets (HELLP). STUDY DESIGN: The pregnancies of 189 patients with HELLP syndrome and delivery <34 weeks' gestation between January 1980 and October 1991 were studied retrospectively. Only patients with class 1 (platelet nadir ≤50,000 per microliter, n = 83) and class 2 (platelet nadir >50,000 to ≤100,000 per microliter, n = 106) HELLP syndrome were included. Maternal and perinatal factors relevant to type of delivery were reviewed. RESULTS: The incidence of cesarean delivery for all patients was 76.2% (primary rate 72.4%). Abdominal delivery occurred equally between class 1 (78.3%) and class 2 (74.5%) patients. Cesarean section was the mode of delivery for 87% of pregnancies at <30 weeks' gestation in contrast to 68% of pregnancies at≥30 weeks but <34 weeks' gestation (odds ratio 3.2, 95% confidence interval 1.4 to 7.5, p < 0.005). Indications for cesarean section included deteriorating maternal condition alone (50%), deteriorating maternal and fetal condition (27%), nonvertex fetal presentation (11.5%), and failure to progress (11%). Induction of labor was significantly more successful during the≥30 but <34 weeks' pregnancy interval (47.5%) than in pregnancies at <30 weeks (15.2%) (odds ratio 0.2, 95% confidence interval 0.1 to 0.55, p < 0.001). A trial of labor was successful in 22% of patients with an initial modified Bishop score ≤2 versus 45% with an initial Bishop >2 (odds ratio 0.5, 95% confidence interval 0.2 to 1.3, p = 0.16). CONCLUSION: Parturients with class 1 and 2 HELLP syndrome at <34 weeks' gestation are at high risk for cesarean delivery. At a gestational age <30 weeks, the likelihood of successful labor induction with vaginal delivery is remote, especially in association with an unfavorable cervix or the absence of labor. (AM J Obstet Gynecol 1994;170:1828-34.)

Elective induction versus spontaneous labor after sonographic diagnosis of fetal macrosomia

OBJECTIVE To test the hypothesis that elective induction of labor, compared to spontaneous labor, reduces the cesarean rate in women with a sonographic diagnosis of fetal macrosomia. METHODS Sonography results over a period of 27 months were used to select 262 consecutive patients who met the following inclusion criteria: singleton pregnancy at term, estimated fetal weight (EFW) at the 90th percentile or greater, and delivery at our institution. The subjects were divided into four groups based on obstetric management: spontaneous labor (N = 115), elective induction of labor with macrosomia as the sole indication (N = 44), induction of labor for other maternal or fetal indications (N = 48), and elective cesarean delivery (N = 55). The analysis focused on the first two groups. These were compared regarding cesarean rate, indications for cesarean, and shoulder dystocia rate. Multiple logistic regression was used to control for potential confounders. RESULTS With elective induction, the cesarean rate was 57%, significantly higher than the 31% rate with spontaneous labor (P < .01). The induced group also had a significantly higher EFW and birth weight. When logistic regression was used to control for birth weight, parity, and care provider, elective induction was still associated with a higher risk of cesarean delivery than was spontaneous labor (adjusted odds ratio 2.7, 95% confidence interval 1.2-5.9; P < .02). Shoulder dystocia occurred in one of 19 vaginal deliveries with elective induction (5.3%) and in two of 79 with spontaneous labor (2.5%). CONCLUSION Because elective induction of labor increased the cesarean rate and did not prevent shoulder dystocia, we conclude that mothers with macrosomic fetuses can safely be managed expectantly unless there is a medical indication for induction.