Epidural analgesia and risks of cesarean and operative vaginal deliveries in nulliparous and multiparous women.

Objective is to examine the effect of epidural analgesia in first stage of labor on occurrence of cesarean and operative vaginal deliveries in nulliparous women and multiparous women without a previous cesarean delivery. Design of the Prospective cohort study. Prenatal care was received at 12 free-standing health centers, 7 private physician offices, or 2 hospital-based clinics; babies were delivered at a free standing birth center or at 3 hospitals, all in San Diego, CA. This study of 2,052 women used data from the San Diego Birth Center Study that enrolled women between 1994 and 1996 to compare the birthing management of the collaborative Certified Nurse Midwife-Medical Doctor Model with that of the traditional Medical Doctor Model. Main Outcome Measures of the Cesarean or operative vaginal deliveries. After adjusting for differences between women who used and those who did not use epidural analgesia in 1st stage of labor, epidural use was associated with a 2.5 relative risk (95% CI: 1.8, 3.4) for operative vaginal delivery in nulliparous women, and a 5.9 relative risk (95% CI: 3.2, 11.1) in multiparous women. Epidural use was associated with a 2.4 relative risk (95% CI: 1.5, 3.7) for cesarean delivery in nulliparous women, and a 1.8 relative risk (95% CI: 0.6, 5.3) in multiparous women. Epidural anesthesia increases the risk for operative vaginal deliveries in both nulliparous and multiparous women, and increases risk for cesarean deliveries in nulliparous more so than in multiparous women.

Transfers among women intending a birth center delivery in the San Diego birth center study.

Using data from the San Diego Birth Center Study that enrolled underserved women between 1994 and 1996, we examined demographic, sociobehavioral, and medical predictors of hospital transfer in a group of women who intended to deliver at a freestanding birth center. Of the 1808 women, 34.6% transferred to the hospital antenatally and 19.6% transferred during labor, while 45.7% delivered at the birth center. Compared with multiparous women who had never had a cesarean and never had a previous hospital delivery, nulliparous women were 2.0 times more likely (95% confidence interval [CI], 1.4-2.7), multiparous women with a previous cesarean were 2.6 times more likely (95% CI, 1.7-3.8), and women without a previous cesarean but who had a previous hospital delivery were 2.1 times more likely (95% CI, 1.5-3.0) to transfer after adjusting for other predictors of transfer. Nulliparity, cesarean history and having a previous hospital delivery were among the strongest predictors of a hospital transfer even after adjusting for demographic, sociobehavioral, and other medical conditions. Understanding predictors of transfer may assist practitioners, patients, and policy makers in considering the appropriateness of individuals for birth center delivery or to target further education to reduce nonmedical transfers.

Maternal epidural analgesia and rates of maternal antibiotic treatment in a low-risk nulliparous population.

BACKGROUND: Epidural analgesia is associated with an increased rate of fever in prospective randomized trials. While the evidence suggests that epidural fever is not infectious, epidural analgesia has been associated with increased rates of antibiotic use, the indications that prompt treatment have not been examined. METHODS: We analyzed 1235 nulliparous women with singleton term pregnancies presenting in labor with a temperature of < 99.5 degrees F. Antibiotic use during labor was categorized by indication. RESULTS: A total of 59.6% of women received epidural analgesia. The rate of antibiotic use was significantly higher in women receiving epidural analgesia (28 vs 10.8%). After adjusting for confounders using logistic regression, epidural analgesia was associated with a relative risk of 2.6 (95% CI 2.0, 3.4) for antibiotic treatment. The majority of the increased risk was due to significantly higher rates of antibiotic treatment for presumed chorioamnionitis (9.0 vs 0.4%) in the epidural analgesia group. CONCLUSION: Epidural-related fever results in excess maternal antibiotic treatment for presumed chorioamnionitis.

Outcomes, safety, and resource utilization in a collaborative care birth center program compared with traditional physician-based perinatal care.

OBJECTIVE: We compared outcomes, safety, and resource utilization in a collaborative management birth center model of perinatal care versus traditional physician-based care. METHODS: We studied 2957 low-risk, low-income women: 1808 receiving collaborative care and 1149 receiving traditional care. RESULTS: Major antepartum (adjusted risk difference [RD] = -0.5%; 95% confidence interval [CI] = -2.5, 1.5), intrapartum (adjusted RD = 0.8%; 95% CI = -2.4, 4.0), and neonatal (adjusted RD = -1.8%; 95% CI = -3.8, 0.1) complications were similar, as were neonatal intensive care unit admissions (adjusted RD = -1.3%; 95% CI = -3.8, 1.1). Collaborative care had a greater number of normal spontaneous vaginal deliveries (adjusted RD = 14.9%; 95% CI = 11.5, 18.3) and less use of epidural anesthesia (adjusted RD = -35.7%; 95% CI = -39.5, -31.8). CONCLUSIONS: For low-risk women, both scenarios result in safe outcomes for mothers and babies. However, fewer operative deliveries and medical resources were used in collaborative care.

Impact of collaborative management and early admission in labor on method of delivery.

OBJECTIVE: This study compared the effects of early admission in labor and perinatal care provider on delivery method. Higher spontaneous vaginal delivery rates for certified nurse midwives as compared with physicians have been reported in observational studies and randomized clinical trials. Certified nurse midwives, with their more expectant approach to labor management, would be expected to admit women later in labor than obstetricians. METHODS: Prospective cohort study of 2,196 low-risk pregnancies, with singleton, vertex infants admitted in spontaneous labor. Independent and joint effects of perinatal care provider and cervical dilation at admission on delivery method were evaluated. Confounding was addressed using restriction and multiple regression. RESULTS: Fewer (23.4%) women in collaborative care were admitted in early labor (< 4 cm cervical dilation) than women managed by obstetricians (95% CI = -27.6 to -19.2). Obstetrician care had 9% to 30% fewer spontaneous vaginal deliveries. Women admitted early in labor also had 6% to 34% fewer spontaneous vaginal deliveries. Evaluation of joint effects suggested that interaction between obstetrician provider and earlier admission increased the risk of operative delivery. CONCLUSION: Later admission in labor (at 4 cm or greater cervical dilation) and management of perinatal care by certified nurse midwives in collaboration with obstetricians increased the rate of spontaneous vaginal delivery in low-risk women.

Differences in systemic opioid use do not explain increased fever incidence in parturients receiving epidural analgesia.

BACKGROUND: It has been hypothesized that an increased incidence of fever in patients receiving epidural analgesia might result not from epidural per se, but rather from the antipyretic effect of opioids preferentially administered to women in the no-epidural group. If this were the case, then one would expect the incidence of fever in parturients who did not receive systemic opioids to be independent of whether they received epidural analgesia. METHODS: Using a cohort study design, the authors evaluated the records of 1,233 nulliparous patients whose labor analgesia was managed with (1) no medication (N = 170); (2) 10 mg intravenous systemic nalbuphine plus 10 mg intramuscular every 3 to 4 h as required (N = 327); (3) epidural analgesia with continuous infusion of 0.125% bupivacaine with 2 microg/ml fentanyl (N = 278); or (4) patients who received both systemic nalbuphine and epidural analgesia (N = 458). Fever was diagnosed if the maximum temperature during labor exceeded 100.4 degrees F (38 degrees C). RESULTS: The incidence of fever did not differ according to nalbuphine administration for women not receiving epidural analgesia (1% no nalbuphine, 0.3% with nalbuphine, P = 0.27) or for women receiving epidural analgesia (17% no nalbuphine, 17% with nalbuphine, P = 1.0). However, the incidence of fever differed significantly between patients who received no analgesia as compared to those who received epidural analgesia alone (1% vs. 17%, P = 10(-6)). Controlling for confounding did not alter these associations. CONCLUSIONS: Our findings suggest that an antipyretic effect of nalbuphine in patients who do not receive an epidural does not explain the greater incidence of fever observed in women who receive epidural analgesia for labor.