Cesarean Delivery In Nulliparous Women Research Articles

Analgesia and cesarean delivery rates: Number 269, February 2002

Various studies report conflicting data with regard to the level of risk of cesarean delivery for nulliparous women who receive epidural analgesia before 5 cm of cervical dilatation. As a result, some institutions are requiring that laboring women reach 4–5 cm of dilatation before receiving epidural analgesia. The American College of Obstetricians and Gynecologists wishes to reaffirm the opinion published jointly with the American Society of Anesthesiologists that while under a physician's care, in the absence of a medical contraindication, maternal request is a sufficient medical indication for pain relief during labor. Decisions regarding analgesia should be coordinated among the obstetrician, the anesthesiologist, the patient, and support personnel.

ACOG committee opinion #269. analgesia and cesarean delivery rates

Various studies report conflicting data with regard to the level of risk of cesarean delivery for nulliparous women who receive epidural analgesia before 5 cm of cervical dilatation. As a result, some institutions are requiring that laboring women reach 4–5 cm of dilatation before receiving epidural analgesia. The American College of Obstetricians and Gynecologists wishes to reaffirm the opinion published jointly with the American Society of Anesthesiologists that while under a physician's care, in the absence of a medical contraindication, maternal request is a sufficient medical indication for pain relief during labor. Decisions regarding analgesia should be coordinated among the obstetrician, the anesthesiologist, the patient, and support personnel.

Body mass index as a risk factor for cesarean delivery in the nulliparous parturient

Objective: To evaluate the relationship between body mass index (BMI) and risk of cesarean delivery in a nulliparous population. Methods: The Mayo Medical Center obstetric delivery database for January 1993 to December 1999 was reviewed to identify all singleton nulliparous women. Height, pregestational weight, BMI, indication, and type of delivery were recorded. Statistical analyses were performed using the Student t test and χ 2 test. Results: Over the study interval, 12,521 deliveries were recorded: 4,302 (34.4%) occurred in nulliparous women with singleton births. Six hundred thirty-nine were excluded for the following reasons: 1) no maternal height recorded (n = 568) or 2) elective cesarean deliveries (n = 71). The overall cesarean rate for the entire study cohort of 3,663 was 17.0%. The cesarean delivery rate was not significantly different (16.9%; 192/1139) for those who underwent labor induction. Interestingly, the cesarean rate was significantly higher in overweight (BMI, 25–29) women (19.1%; 128/659) ( P = 0.038) and obese (BMI, > 29) women (23.6%; 124/525) ( P <0.0001) as compared with women of normal weight (BMI, 20–24.9) (15.5%; 296/1905). The cesarean rate in women with low BMI (<20) was lower (13.4%; 77/574); however, this was not significantly different from the rate observed in women of normal weight. Conclusion: Increased BMI is a risk factor for cesarean delivery in nulliparous women.

Maternal height as a risk factor for cesarean delivery in the nulliparous parturient

Objective: To evaluate the relationship between maternal height and risk of cesarean delivery in a nulliparous population. Methods: The Mayo Medical Center obstetric delivery database from January 1993 to December 1999 was reviewed to identify all singleton nulliparous women. Height (ht), indication, and type of delivery were recorded. Statistical analyses were performed using the Student t test and X 2. Results: Over the study interval, 12,521 deliveries were recorded: 4,302 (34.4%) occurred in the nulliparous women with singletons. Six hundred thirty-nine deliveries were excluded for the following: 1) no maternal ht recorded (n = 568), and 2) elective cesarean deliveries (n =71). The overall cesarean delivery rate for the entire study cohort of 3,663 was 17.0%. The cesarean delivery rate was not significantly different (16.9%; [192/1,139]) for those who underwent labor induction. Overall maternal ht was significantly different between women who had a cesarean delivery after labor (163.1 ± 6.9 cm) and those who delivered vaginally (164.5 ± 7.0 cm) ( P <0.0001). The cesarean delivery rate was significantly higher in women with short stature as compared with the entire study cohort: 23.5% (54/230) in women with ht less than 152.4 cm (5’) ( P = 0.017); 22.3% (167/750) in women with ht less than 157.5 cm (5’ 2‘) ( P = 0.001); and 18.8% (423/2252) in women with ht less than 165.1 cm (5’ 5‘) ( P = NS). A similar trend was noted for women whose labor was induced; however, this trend was not statistically significant. Conclusion: Short maternal stature is a risk factor for cesarean delivery in nulliparous women.

The effect of the obstetrician group and epidural analgesia on the risk for cesarean delivery in nulliparous women.

The effects of regional anesthesia and of the obstetrician on the risk of cesarean delivery remain controversial. The purpose of this study was to determine whether epidural analgesia or the obstetrician group is associated with an increase in the risk for cesarean delivery in nulliparous women. Data were collected for a two-year period from the medical records of all nulliparous women who had a private obstetrician who delivered >20 babies per year, and who presented with a singleton gestation in the vertex presentation for a trial of labor. Data were collected for 3699 women of whom 1832 were nulliparous. Of the 1832 nulliparous women, data were analyzed for the 1278 women who met our study criteria, representing 14 separate obstetrician groups. Excluding the 50 women whose babies were delivered for fetal distress (leaving 1228 women for analysis), the epidural rate was 93%, range 81-98%, and the cesarean delivery rate was 14%, range 8-34%. Logistic regression analyses revealed that (odds ratio, 95% confidence interval) patient age (1.7, 1.2-2.4), birth weight (1.001, 1.001-1.002), induction of labor (1.9, 1.3-2.7), non-Caucasian (1.9, 1.2-2.9) and the obstetrician group, (P=0.002), were independently associated with the risk of cesarean delivery, but epidural analgesia was not (1.6, 0.7-3.6). The obstetrician group is independently associated with the risk of cesarean delivery in nulliparous women, but we could not demonstrate this association with epidural analgesia. We suggest that in future studies regarding epidural analgesia and cesarean delivery, the obstetrician group should be included as a variable.

Maternal birth weight and cesarean delivery in four race-ethnic groups

Objective: We hypothesized that maternal birth weight was associated with the risk of cesarean delivery for nulliparous women. Study Design: In a population-based cohort study, maternal birth data were linked to a Washington State database, including the birth certificates of 18,905 first-born singleton infants (1987-1995). Results: Among non-Hispanic white subjects, maternal birth weight of 2500 to 3999 g was associated with a 20.9% risk of cesarean delivery, which was the lowest risk, compared with 24.5% for a maternal birth weight <2500 g (P <.05) and 24.0% for a maternal birth weight ≥4000 g (P <.05). Similar patterns of risk were noted among Hispanic and Native American subjects, although the associations did not reach statistical significance. Risk of cesarean delivery was not associated with maternal birth weight among African American subjects. Among non-Hispanic white subjects, the risk of cesarean delivery was 3.23 times greater with a maternal birth weight <2500 g and an infant birth weight ≥4000 g compared with pregnancies with both maternal and infant birth weights between 2500 and 3999 g (P <.001). Adjustment for socioeconomic factors did not alter these results. Conclusion: Low and high maternal birth weights exert an intergenerational risk of cesarean delivery in nulliparous non-Hispanic white women. (Am J Obstet Gynecol 2000;182:1363-70.)

Randomized controlled comparison of epidural bupivacaine versus pethidine for analgesia in labour

We compared the incidence of Caesarean delivery in nulliparous women randomized to receive epidural analgesia with those randomized to intramuscular (i.m.) pethidine. On admission to the delivery suite in established labour, 802 nulliparae had already agreed to be randomized with respect to their first analgesia. One hundred and eighty-eight women required either no analgesia or 50% nitrous oxide in oxygen (Entonox) only. Of the remaining 614 women, 310 were randomly allocated to receive i.m. pethidine up to 300 mg and 304 to receive epidural bupivacaine. Labour management was standardized according to the criteria for active management of labour. The intention-to-treat analysis showed similar Caesarean section rates in those randomized to epidural (12%) or pethidine analgesia (13%). The difference in Caesarean rate was -1.1% with 95% confidence intervals from -6.3% to +4.1%. The normal vaginal delivery rates were similar (epidural, 59%; pethidine, 61%).

Exercise During Pregnancy and Type of Delivery in Nulliparae

To assess the association between participation in aerobic exercise during the first two trimesters of pregnancy and type of delivery in nulliparous women. Nonexperimental, retrospective. A large metropolitan area in the southwestern United States. 137 nulliparous women. Method of delivery. An unadjusted odds ratio showed that sedentary women (n = 93) were 2.05 times more likely to deliver via cesarean section than active women (n = 44), but this relationship was not statistically significant. Through logistic regression analysis with control for the mother's prepregnancy exercise program, age, use of epidural anesthesia, change in prepregnancy to delivery body mass index, labor length, whether labor was induced, and the hospital of birth, the odds of cesarean delivery were found to be 4.5 times greater for sedentary women than for active women. Regular participation in physical activity during the first two trimesters of pregnancy may be associated with reduced risk for cesarean delivery in nulliparous women.

Risk of cesarean delivery with elective induction of labor at term in nulliparous women

Objective: To quantify the risk of cesarean delivery associated with elective induction of labor in nulliparous women at term. Methods: We performed a cohort study on a major urban obstetric service that serves predominantly private obstetric practices. All term, nulliparous women with vertex, singleton gestations who labored during an 8-month period ( n = 1561) were divided into three groups: spontaneous labor, elective induction, and medical induction. The risk of cesarean delivery in the induction groups was determined using stepwise logistic regression to control for potential confounding factors. Results: Women experiencing spontaneous labor had a 7.8% cesarean delivery rate, whereas women undergoing elective labor induction had a 17.5% cesarean delivery rate (adjusted odds ratio [OR] 1.89; 95% confidence interval [CI] 1.12, 3.18) and women undergoing medically indicated labor induction had a 17.7% cesarean delivery rate (OR 1.69; 95% CI 1.13, 2.54). Other variables that remained significant risk factors for cesarean delivery in the model included: epidural placement at less than 4 cm dilatation (OR 4.66; 95% CI 2.25, 9.66), epidural placement after 4 cm dilatation (OR 2.18; 95% CI 1.06, 4.48), chorioamnionitis (OR 4.61; 95% CI 2.89, 7.35), birth weight greater than 4000 g (OR 2.59; 95% CI 1.69, 3.97), maternal body mass index greater than 26 kg/m 2 (OR 2.36; 95% CI 1.61, 3.47), Asian race (OR 2.35; 95% CI 1.04, 5.34), and magnesium sulfate use (OR 2.18; 95% CI 1.04, 4.55). Conclusion: Elective induction of labor is associated with a significantly increased risk of cesarean delivery in nulliparous women. Avoiding labor induction in settings of unproved benefit may aid efforts to reduce the primary cesarean delivery rate.

Risk of Cesarean Delivery With Elective Induction of Labor at Term in Nulliparous Women

In Brief Objective To quantify the risk of cesarean delivery associated with elective induction of labor in nulliparous women at term. Methods We performed a cohort study on a major urban obstetric service that serves predominantly private obstetric practices. All term, nulliparous women with vertex, singleton gestations who labored during an 8-month period (n = 1561) were divided into three groups: spontaneous labor, elective induction, and medical induction. The risk of cesarean delivery in the induction groups was determined using stepwise logistic regression to control for potential confounding factors. Results Women experiencing spontaneous labor had a 7.8% cesarean delivery rate, whereas women undergoing elective labor induction had a 17.5% cesarean delivery rate (adjusted odds ratio [OR] 1.89; 95% confidence interval [CI] 1.12, 3.18) and women undergoing medically indicated labor induction had a 17.7% cesarean delivery rate (OR 1.69; 95% CI 1.13, 2.54). Other variables that remained significant risk factors for cesarean delivery in the model included: epidural placement at less than 4 cm dilatation (OR 4.66; 95% CI 2.25, 9.66), epidural placement after 4 cm dilatation (OR 2.18; 95% CI 1.06, 4.48), chorioamnionitis (OR 4.61; 95% CI 2.89, 7.35), birth weight greater than 4000 g (OR 2.59; 95% CI 1.69, 3.97), maternal body mass index greater than 26 kg/m2 (OR 2.36; 95% CI 1.61, 3.47), Asian race (OR 2.35; 95% CI 1.04, 5.34), and magnesium sulfate use (OR 2.18; 95% CI 1.04, 4.55). Conclusion Elective induction of labor is associated with a significantly increased risk of cesarean delivery in nulliparous women. Avoiding labor induction in settings of unproved benefit may aid efforts to reduce the primary cesarean delivery rate. The elective induction of nulliparous women at term is associated with nearly a two-fold increase in the risk of cesarean delivery compared with nulliparous women undergoing spontaneous labor.

Electronic monitor versus palpation: Seitchik J, Rao V: Cesarean delivery in nulliparous women for failed oxytocin-augmented labor: Route of delivery in subsequent pregnancy. Am J Obstet Gynecol 143:393, 1982

Electronic monitor versus palpation: Seitchik J, Rao V: Cesarean delivery in nulliparous women for failed oxytocin-augmented labor: Route of delivery in subsequent pregnancy. Am J Obstet Gynecol 143:393, 1982

Cesarean delivery in nulliparous women for failed oxytocin-augmented labor: Route of delivery in subsequent pregnancy

Fifty-eight patients experienced cesarean section for termination of their first term pregnancy subsequent to a failed trial of oxytocin therapy. Cephalopelvic disproportion and “failure to progress” were the sole indications for the initial cesarean section. All 58 women returned to our hospital for a subsequent trial of labor during the years 1977–1979 inclusive, and 40 of the 58 were able to have a vaginal delivery. Parameters investigated included first and subsequent pregnancy birth weights; birth weight difference; duration and maximal dose of oxytocin; status of the cervix at admission, prior to oxytocin, and before cesarean section; and the clinical and/or radiologic estimation of pelvic dimensions. Subsequent brith weight < 3,500 gm was the only statistically significant factor associated with a high rate of vaginal delivery.