Search

Focuses on the issues concerning delivery after one previous cesarean section. Factors that influence the escalation of total cesarean section rate; Recommendation on the use of the transverse uterine segment in cesarean section surgery; Statistics on the modes of delivery after one previous cesarean section.

Background: In contemporary practice many nulliparous women require intervention during childbirth such as operative vaginal delivery or cesarean delivery (CD). Despite the knowledge that the increasing rate of CD is associated with increasing maternal age, obesity and larger infant birthweight, we lack a reliable method to predict the requirement for such potentially hazardous obstetric procedures during labor and delivery. This issue is important, as there are greater rates of morbidity and mortality associated with unplanned CD performed in labor compared with scheduled CDs. A prediction algorithm to identify women at risk of an unplanned CD could help reduced labor associated morbidity.Objective: In this primary analysis of the Genesis study, our objective was to prospectively assess the use of prenatally determined, maternal and fetal, anthropomorphic, clinical, and ultrasound features to develop a predictive tool for unplanned CD in the term nulliparous woman, before the onset of labor.Materials and Methods: The Genesis study recruited 2336 nulliparous women with a vertex presentation between 39+0 and 40+6 weeks' gestation in a prospective multicenter national study to examine predictors of CD. At recruitment, a detailed clinical evaluation and ultrasound assessment were performed. To reduce bias from knowledge of these data potentially influencing mode of delivery, women, midwives, and obstetricians were blinded to the ultrasound data. All hypothetical prenatal risk factors for unplanned CD were assessed as a composite. Multiple logistic regression analysis and mathematical modeling was used to develop a risk evaluation tool for CD in nulliparous women. Continuous predictors were standardized using z scores.Results: From a total enrolled cohort of 2336 nulliparous participants, 491 (21%) had an unplanned CD. Five parameters were determined to be the best combined predictors of CD. These were advancing maternal age (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.09 to 1.34), shorter maternal height (OR, 1.72; 95% CI, 1.52 to 1.93), increasing body mass index (OR, 1.29; 95% CI, 1.17 to 1.43), larger fetal abdominal circumference (OR, 1.23; 95% CI, 1.1 to 1.38), and larger fetal head circumference (OR, 1.27; 95% CI, 1.14 to 1.42). A nomogram was developed to provide an individualized risk assessment to predict CD in clinical practice, with excellent calibration and discriminative ability (Kolmogorov-Smirnov, D statistic, 0.29; 95% CI, 0.28 to 0.30) with a misclassification rate of 0.21 (95% CI, 0.19 to 0.25).Conclusion: Five parameters (maternal age, body mass index, height, fetal abdominal circumference, and fetal head circumference) can, in combination, be used to better determine the overall risk of CD in nulliparous women at term. A risk score can be used to inform women of their individualized probability of CD. This risk tool may be useful for reassuring most women regarding their likely success at achieving an uncomplicated vaginal delivery as well as selecting those patients with such a high risk for CD that they should avoid a trial of labor. Such a risk tool has the potential to greatly improve planning hospital service needs and minimizing patient risk. [ABSTRACT FROM AUTHOR]

Objective: In the prospective multicenter Genesis study, we developed a prediction model for Cesarean delivery (CD) in term nulliparous women. The objective of this secondary analysis was to determine whether the Genesis model has the potential to predict maternal and neonatal morbidity associated with vaginal delivery.Study Design: The national prospective Genesis trial recruited 2,336 nulliparous women with a vertex presentation between 39 + 0- and 40 + 6-weeks' gestation from seven tertiary centers. The prediction model used five parameters to assess the risk of CD: maternal age, maternal height, body mass index, fetal head circumference and fetal abdominal circumference. Simple and multiple logistic regression analyses were used to develop the Genesis model. The risk score calculated using this model were correlated with maternal and neonatal morbidity in women who delivered vaginally: postpartum hemorrhage (PPH), obstetric anal sphincter injury (OASI), shoulder dystocia, one- and five-minute Apgar score ≤ 7, neonatal intensive care (NICU) admission, cephalohematoma, fetal laceration, nerve palsy and fractures. The morbidities associated with spontaneous vaginal delivery were compared with those associated with operative vaginal delivery (OVD). The likelihood ratios for composite morbidity and the morbidity associated with OVD based on the Genesis risk scores were also calculated.Results: A total of 1,845 (79%) nulliparous women had a vaginal delivery. A trend of increasing intervention and morbidity was observed with increasing Genesis risk score, including OVD (p < 0.001), PPH (p < 0.008), NICU admission (p < 0.001), low Apgar score at one-minute (p < 0.001) and OASI (p = 0.009). The morbidity associated with OVD was significantly higher compared to spontaneous vaginal delivery, including NICU admission (p < 0.001), PPH (p = 0.022), birth injury (p < 0.001), shoulder dystocia (p = 0.002) and Apgar score of<7 at one-minute (p < 0.001). The positive likelihood ratios for composite outcomes (where the OVD was excluded) increases with increasing risk score from 1.005 at risk score of 5% to 2.507 for risk score of>50%.Conclusion: In women who ultimately achieved a vaginal birth, we have shown more maternal and neonatal morbidity in the setting of a Genesis nomogram-determined high-risk score for intrapartum CD. Therefore, the Genesis prediction tool also has the potential to predict a more morbid vaginal delivery. [ABSTRACT FROM AUTHOR]

Objectives: To determine the incidence of maternal morbidity following elective caesarean section in women with a history of at least two previous caesarean sections, and to determine if the incidence of morbidity correlates with the number of previous sections. Study design: We conducted an individual chart review of all women who had an elective caesarean section because of a history of two previous sections from 1990 to 1999. Results: There were 67,097 deliveries of babies weighing 500 g or more. The total number of cases eligible for the study was 250. There were 12 cases (4.8%) of placenta praevia of which four required a transfusion and two a hysterectomy. The incidence of wound infection was 6.3% and urinary tract infection was 11.2%. There were no cases of thromboembolism recorded. Conclusions: Maternal morbidity with elective repeat caesarean section is low. The major morbidity is associated with placenta praevia. We found no correlation between the incidence of maternal morbidity and the number of previous sections. [Copyright &y& Elsevier]

Objective: Contemporary approaches to monitoring quality of care in obstetrics often focus on comparing Cesarean Delivery rates. Varied rates can complicate interpretation of quality of care. We previously developed a risk prediction tool for nulliparous women who may require intrapartum Cesarean delivery which identified five key predictors. Our objective with this study was to ascertain if patient heterogeneity can account for much of the observed variation in Cesarean delivery rates, thereby enabling Cesarean delivery rates to be a better marker of quality of care.Materials and Methods: This is a secondary analysis of the Genesis study. This was a large prospective study of 2336 nulliparous singleton pregnancies recruited at seven hospitals. A heterogeneity score was calculated for each hospital. An adjusted Cesarean delivery rate was also calculated incorporating the heterogeneous risk score.Results: A cut-off at the 90th percentile was determined for each predictive factor. Above the 90th percentile was considered to represent 'high risk' (with the exception of maternal height which identified those below the 10th percentile). The patient heterogeneous risk score was defined as the number of risk factors > 90th percentile (<10th percentile for height). An unequal distribution of high-risk patients between centers was observed (p < 0.001). The correlation between the Cesarean delivery rate and the patient heterogeneous risk score was high (0.76, p < 0.05). When adjusted for patient heterogeneity, Cesarean delivery rates became closer aligned.Conclusion: Inter-institutional diversity is common. We suggest that crude comparison of Cesarean delivery rates between different hospitals as a marker of care quality is inappropriate. Allowing for marked differences in patient characteristics is essential for correct interpretation of such comparisons. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to examine the implications of increased maternal Breath Carbon Monoxide (BCO) levels at the first antenatal visit for subsequent birthweight (BW) and neonatal outcomes.Study Design: Secondary analysis of a prospective, observational study. Pregnant women aged ≥18years who understood English were recruited (n=250). However, only women who delivered a normally formed baby weighing ≥500g were analysed (n=234). At the first antenatal visit, a research questionnaire was completed and a BCO test was performed. Obstetric and neonatal data computerised by midwives at the first antenatal visit and updated after delivery were also analysed.Results: Results from the receiver operating characteristic (ROC) curve indicated the highest combined sensitivity and specificity for smoking was observed at a BCO cut-off level of 3ppm (sensitivity 85%, specificity 90%). Of the 234 women, 53 (22.6%) had a BCO ≥3ppm but only 36 (15.4%) disclosed smoking to the midwife on routine questioning. A further 23 (9.8%) were classified as non-disclosers based on a research questionnaire and/or a BCO measurement ≥3ppm. No relationship was found between the self-reported number of cigarettes daily in early pregnancy and BW (r=0.05, p=0.78). However, an inverse relationship was found between maternal BCO levels and BW (r=-0.31, p<0.001). BCO levels ≥3ppm in early pregnancy were associated with an increased risk of emergency caesarean section, low birth weight, BW <25th centile, fetal distress and having two or more adverse pregnancy events (all p<0.05). Smoking non-disclosers had babies with decreased BWs (-400.1g, 95% CI 141.1-659.0g, p<0.001), and higher rates of BW <25th centile (56.5% versus 25.3%, p<0.001), small-for-gestational-age (21.7% versus 9.1%, p<0.001) and fetal distress (39.1% versus 16.0%, p<0.01) compared to non-smokers Non-disclosers at the first antenatal visit also had a 22% higher rate of having two or more adverse pregnancy events (p<0.05).Conclusion: The results showed that an increased BCO level was associated with a lower BW and increased risk of adverse pregnancy and neonatal outcomes. This strengthens the case for universal BCO screening at the first antenatal visit. A high BCO reading should be an indication for referral to stop smoking services referral and close fetal surveillance. [ABSTRACT FROM AUTHOR]

Abstract: Objective: This study looked at the association between caesarean section (CS) and Body Mass Index (BMI) in primigravidas compared with multigravidas. Study design: We enrolled women at their convenience, in the first trimester after an ultrasound examination confirmed an ongoing pregnancy. Weight and height were measured digitally and BMI calculated. After delivery, clinical details were again collected from the Hospital''s computerised database. Results: Of the 2000 women enrolled, there were 50.4% (n =1008) primigravidas and 49.6% (n =992) multigravidas. Of the 2000 8.5% were delivered by elective CS and 13.4% were delivered by emergency CS giving an overall rate of 21.9%. The overall CS rate was 30.1% in obese women compared with 19.2% in the normal BMI category (p <0.001). In primigravidas the increase in CS rate in obese women was due to an increase in emergency CS (p <0.005) and in multigravidas the increase was due to an increase in elective CS (p <0.01). In obese primigravidas 20.6% had an emergency section for fetal distress. In obese multigravidas 17.2% had a repeat elective CS. Conclusion: The influence of maternal obesity on the increase in CS rates is different in primigravidas compared with multigravidas. [Copyright &y& Elsevier]