Difference In Cesarean Delivery Rate Research Articles

Maternal and Neonatal Outcomes with One Abnormal Value on 100g Three Hour Glucose Tolerance Test in Pregnancy

Purpose: The primary objective of this study was to compare pregnancy outcomes for patients with no elevated glucose values, one elevated glucose value, and 2 or more elevated glucose values on the 3-hour glucose tolerance test (GTT). Methods: This was a retrospective chart review of obstetric patients seen by residents and attending physicians at a single institution from 2015 to 2020 who were required to complete a 3-hour glucose tolerance test (GTT). Data extracted from the maternal chart included demographic information, BMI, route of delivery, presence of preeclampsia, chorioamnionitis, shoulder dystocia and preterm labor. Data extracted from the neonatal chart included blood glucose level after birth, birth weight, Apgar scores, and if NICU admission was required. Continuous data were analyzed using one-way ANOVA to compare the 3 groups, followed by post-hoc Tukey HSD to compare the 1 abnormal value group to the control group. Dichotomous data were analyzed using Chi square tests. Logistic regression was performed using shoulder dystocia as the outcome. Results: Patients with two or more elevated GTT values had higher age and BMI and were more likely to be prescribed diabetic medications compared to those with normal or one elevated value. They were also more likely to deliver at an earlier gestational age. Patients with one elevated GTT value experienced a statistically significant higher chance of shoulder dystocia compared to patients with all normal GTT results (OR 2.34; 95% CI 1.05, 5.20). Patients with two or more elevated values were more likely to have preeclampsia and a neonate requiring NICU admission. There were no differences in cesarean delivery rate, hemorrhage or chorioamnionitis between the groups. Conclusions: Patients with one elevated GTT value are a special subset of patients who do not meet criteria for gestational diabetes, yet do not have normal glucose testing results. We hypothesize that this group is at higher risk of shoulder dystocia because these patients may have hyperglycemia but often do not receive the same type of monitoring, dietary education, medication initiation and induction timing as patients who meet criteria for gestational diabetes.

The Relationship of Patient/Provider Racial Concordance to Nulliparous, Term, Singleton, Vertex Cesarean Delivery Rates [ID 2683595

INTRODUCTION: Prior studies have explored factors affecting nulliparous, term, singleton, vertex cesarean (NTSV-C) delivery rates, such as induction, provider type, and racial disparities. Some studies have shown higher NTSV-C rates among non-White patients compared to their White counterparts. Our aim was to study the influence of racial concordance between patient and provider on NTSV outcomes. METHODS: A retrospective analysis of 315 NTSV pregnancies at an urban hospital from January to March 2023 was performed. The NTSV outcomes by racial concordance were examined using χ2 and Fisher exact tests with alpha <.05. Logistic regression analysis was used to adjust for high-risk maternal comorbidities. The race of patients and delivering providers was based on self-identification. RESULTS: A majority of patient–provider dyads were concordant for race (199/315 [63.2%]). Racial concordance was associated with a lower NTSV-C rates (23.1 versus 33.6%; P=.04). This association persisted after adjusting for maternal comorbidities (P=.003). When NTSV outcomes were stratified by patient race, significant differences in cesarean delivery rates by patient race were observed for White providers (P=.02). No significant differences between races were observed for Asian (P=.93) or Black providers (P=.82). CONCLUSION: These results emphasize the significant effect of racial concordance between patients and providers on cesarean delivery rates, highlighting the need for further examination of health care disparities and tailored interventions to promote equitable maternal care.

Timing of induction of labor in suspected macrosomia: retrospective cohort study, systematic review and meta-analysis.

Large-for-gestational-age (LGA) is associated with several adverse maternal and neonatal outcomes. Although many studies have found that early induction of labor (eIOL) in LGA reduces the incidence of shoulder dystocia (SD), no current guidelines recommend this particular strategy, due to concerns about increased rates of cesarean delivery (CD) and neonatal complications. The purpose of this study was to assess whether the timing of IOL in LGA fetuses affects maternal and neonatal outcomes in a single center; and to combine these results with the evidence reported in the literature. This study comprised two parts. The first was a retrospective cohort study that included: consecutive patients with singleton pregnancy, an estimated fetal weight (EFW) ≥90th percentile on ultrasound (US) between 35+0 and 39+0 weeks of gestation (WG), who were eligible for normal vaginal delivery. The second part was a systematic review of literature and meta-analysis that included the results of the first part as well as all previously reported studies that have compared IOL to expectant management in patients with LGA. The perinatal outcomes were CD, operative vaginal delivery (OVD), SD, brachial plexus palsy, anal sphincter injury, postpartum hemorrhage (PPH), APGAR score, umbilical arterial pH, neonatal intensive care unit (NICU) admission, use of continuous positive airway pressure (CPAP), intracranial hemorrhage (ICH), phototherapy, and bone fracture. Retrospective cohort: of the 547 patients, 329 (60.1%) were induced and 218 (39.9%) entered spontaneous labor. Following covariate balancing, CD was significantly higher in the IOL group in comparison to the spontaneous labor group. This difference only became apparent beyond 40WG (hazard ratio: 1.9, p=0.030). The difference between both groups for shoulder dystocia was not statistically significant. Systematic review and metanalysis: 17 studies were included in addition to our own results giving a total sample size of 111,300 participants. When IOL was performed <40+0WG, the risk for SD was significantly lower in the IOL group (OR: 0.64, 95%CI: 0.42-0.98, I2 =19%). There was no significant difference in CD rate between IOL and expectant management after pooling the results of these 17 studies. However, when removing the studies in which IOL was done exclusively before 40+0WG, the risk for CD in the remaining studies (IOL not exclusively <40+0WG) was significantly higher in the IOL group (odds ratio [OR]: 1.46, 95% confidence interval [95%CI]: 1.02-2.09, I2 =56%). There were no statistically significant differences between IOL and expectant management for the remaining perinatal outcomes. Nulliparity, history of CD, and low Bishop score but not methods of induction were independent risk factors for intrapartum CD in patients who were induced for LGA. Timing of IOL in patients with suspected macrosomia significantly impacts perinatal adverse outcomes. IOL has no impact on rates of SD but does increase CD when considered irrespective of gestational age, but it may decrease the risk of SD without increasing the risk of other adverse maternal outcomes, in particular cesarean section when performed before 40+0 WG. (GRADE: Low/Very low). This article is protected by copyright. All rights reserved.

Just Pop It: Early AROM After Cervical Ripening Reduces the Time to Delivery.

In pregnant patients at term undergoing induction of labor, early time-based artificial rupture of membranes (AROM) within 1 hour of Foley bulb expulsion results in a shorter duration of labor by nearly 9 hours with no significant difference in cesarean delivery rates or maternal or neonatal adverse outcomes.1.

Efficacy of Propranolol to Reduce Cesarean Delivery in Prolonged Labor: A Randomized Controlled Trial.

To evaluate the rates of cesarean delivery in patients with prolonged labor randomized to receive intravenous (IV) propranolol compared with placebo. A double-blind, placebo-controlled, randomized trial was conducted at two hospitals within a large academic health system. Eligible patients were at 36 weeks or more with a singleton gestation and prolonged labor , defined as: 1) prolonged latent phase of labor (dilation less than 6 cm after 8 hours or more with ruptured membranes and receiving oxytocin infusion) or 2) prolonged active phase of labor (dilation 6 cm or greater and less than 1-cm cervical dilation change over 2 hours or more with ruptured membranes and receiving oxytocin infusion). Patients were excluded for severe preeclampsia, maternal heart rate less than 70 beats per minute, maternal blood pressure less than 90/50 mm Hg, asthma, diabetes requiring insulin during labor, or a cardiac contraindication to β-blockade. Patients were randomized to propranolol (2 mg IV) compared with placebo (2 mL normal saline IV), with one possible repeat dose. The primary outcome was cesarean delivery; secondary outcomes included labor duration, shoulder dystocia, and maternal and neonatal morbidity. With an estimated cesarean delivery rate of 45%, α 0.05, and 80% power, we required 163 patients per group to detect a 15% absolute reduction in cesarean delivery rate. A planned interim analysis was performed, and the trial was stopped for futility. From July 2020 to June 2022, 349 patients were eligible and approached; 164 were enrolled and randomized, with 84 in the propranolol group and 80 in the placebo group. The rate of cesarean delivery was not different between groups (57.1% propranolol vs 57.5% placebo, relative risk [RR] 0.99, 95% CI 0.76-1.29). Results were similar by subgroup of prolonged latent (n=123) and active (n=41) phases of labor and nulliparous (n=137) and multiparous (n=27) patients. Though not statistically significant, the frequency of postpartum hemorrhage was higher in the propranolol group (20% vs 10%, RR 2.02, 95% CI 0.93-4.43). In this multisite, double-blind, placebo-controlled randomized trial, there was no difference in cesarean delivery rate for patients who received propranolol compared with those who received placebo for management of prolonged labor. ClinicalTrials.gov , NCT04299438.

Adverse Maternal Outcomes Associated With Gestational Weight Gain in Women With Polycystic Ovarian Syndrome [ID: 1377702

INTRODUCTION: The objective of this study was to investigate maternal complications associated with gestational weight gain (GWG) in women with a history of polycystic ovarian syndrome (PCOS). METHODS: This was a retrospective cohort analysis using data abstracted from the California Office of Statewide Health Planning and Development (OSHPD) Linked Birth File with hospital discharge International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnoses between 2007 and 2012. Pregnancies in women with a history of PCOS were stratified based on the Institute of Medicine 2009 recommendations for GWG as follows: appropriate weight gain, excessive weight gain, inadequate weight gain, or weight loss. The maternal outcomes of interest included preeclampsia, cesarean delivery, blood transfusion, and intensive care admission. Logistic regression analysis was performed to estimate the odd ratio of the outcomes of interest for each GWG stratum in pregnancies with and without PCOS, with adjustments for confounding variables. RESULTS: There were 3,161,821 pregnancies, with 4,233 women with history of PCOS. The risk of cesarean delivery for women in the excessive weight gain cohort without PCOS was 1.35% versus 1.68% in the PCOS group (P&lt;.001, 95% CI [1.38–2.04]). There were no significant differences in cesarean delivery rate for women with PCOS in the inadequate weight gain or weight loss groups. There were no statistically significant differences for preeclampsia, blood transfusion, and intensive care admission in pregnancies with and without PCOS based on GWG. CONCLUSION: In pregnancies affected by PCOS, excessive weight gain is associated with increased risk of cesarean delivery compared to women without PCOS.

Labor Induction Outcomes with Outpatient Misoprostol for Cervical Ripening among Low-Risk Women.

In 2012, two Kaiser Permanente Northern California (KPNC) hospitals began offering outpatient cervical ripening with oral misoprostol under a study protocol. We evaluated inpatient time from admission to delivery and adverse maternal and neonatal outcomes associated with outpatient use of misoprostol for cervical ripening among low-risk women with term pregnancies. We conducted a retrospective cohort study comparing three groups: women who received misoprostol (1) outpatient, under a study protocol; (2) inpatient, at the study sites; and (3) inpatient, at all KPNC hospitals. Data were obtained from between 2012 and 2017. The primary outcome was time from inpatient admission to delivery. Secondarily, we evaluated maternal and neonatal outcomes, including the duration and maximum rate of oxytocin administered, rate of cesarean delivery, incidence of chorioamnionitis and blood transfusion, Apgar scores, and neonatal intensive care unit admissions. Demographic and clinical characteristics and outcomes of the outpatient group were compared with both inpatient misoprostol groups using the appropriate statistical test. Variables included in the regression analysis were either statistically significant in the bivariate analyses or have been reported in the literature to be potential confounders: maternal age at admission, race/ethnicity, body mass index, cervical dilation at initial misoprostol, and parity. We analyzed data from 10,253 patients: (1) 345 outpatients, under a study protocol; (2) 1,374 inpatients, at the study sites; and (3) 9,908 inpatients, at all the Kaiser hospitals. Women in the outpatient group were more likely to be white than both inpatient groups (63.3 vs. 56.3% at study sites and 47.1% in all hospitals, p = 0.002 and <0.001, respectively); other demographics were clinically comparable. Most women undergoing labor induction were nulliparous; however, a greater proportion in the outpatient group were nulliparous compared with inpatient groups (70.8 vs. 61.8% and 64.3%, p = 0.002 and 0.01). On inpatient admission for delivery, women who received outpatient misoprostol were more likely to have a cervical dilation of ≥3 cm (39.8 vs. 12.5% at study sites and 9.7% at all KPNC hospitals, p < 0.001 for both). The outpatient group had a shorter mean time between admission and delivery (23.6 vs. 29.4 at study sites and 29.8 hours at all KPNC, p < 0.001 for both). The adjusted estimated mean difference between the outpatient and inpatient group at all the Kaiser hospitals in time from admission to delivery was -6.48 hours (p < 0.001), and the adjusted estimated mean difference in cervical dilation on admission was +1.02 cm (p < 0.001). There was no difference in cesarean delivery rates between groups. The rate of chorioamnionitis in the outpatient group was higher compared with inpatients at all hospitals (17.7 vs. 10.6%, p < 0.001), but similar when compared with the inpatients at the study sites (17.7 vs. 15.4%, p = 0.29). Outpatient use of misoprostol for cervical ripening under the study protocol was associated with reduced inpatient time from admission to delivery compared with inpatient misoprostol. Although there was a higher rate of chorioamnionitis among outpatients under the study protocol compared with inpatients at all hospitals, there was no difference when compared with inpatients at the study sites. There was no difference in rates of cesarean delivery or maternal or neonatal complications with outpatient misoprostol. · Outpatient misoprostol patients had 6.46 fewer hours from admission to delivery compared with inpatients at all hospitals.. · There was no difference in the rate of cesareans between the outpatient versus inpatient misoprostol groups.. · Other maternal and neonatal complications were low and comparable among outpatients and inpatients who received misoprostol; this study was not large enough to assess rare safety outcomes..

Crude and adjusted comparisons of cesarean delivery rates using the Robson classification: A population-based cohort study in Canada and Sweden, 2004 to 2016

The Robson classification has become a global standard for comparing and monitoring cesarean delivery (CD) rates across populations and over time; however, this classification does not account for differences in important maternal, fetal, and obstetric practice factors known to impact CD rates. The objectives of our study were to identify subgroups of women contributing to differences in the CD rate in Sweden and British Columbia (BC), Canada using the Robson classification and to estimate the contribution of maternal, fetal/infant, and obstetric practice factors to differences in CD rates between countries and over time. We conducted a population-based cohort study of deliveries in Sweden (January 1, 2004 to December 31, 2016; n = 1,392,779) and BC (March 1, 2004 to April 31, 2017; n = 559,205). Deliveries were stratified into Robson categories and the CD rate, relative size of each group and its contribution to the overall CD rate were compared between the Swedish and the Canadian cohorts. Poisson and log-binomial regression were used to assess the contribution of maternal, fetal, and obstetric practice factors to spatiotemporal differences in Robson group-specific CD rates between Sweden and BC. Nulliparous women comprised 44.8% of the study population, while women of advanced maternal age (≥35 years) and women with overweight/obesity (≥25 kg/m2) constituted 23.5% and 32.4% of the study population, respectively. The CD rate in Sweden was stable at approximately 17.0% from 2004 to 2016 (p for trend = 0.10), while the CD rate increased in BC from 29.4% to 33.9% (p for trend < 0.001). Differences in CD rates between Sweden and BC varied by Robson group, for example, in Group 1 (nullipara with a term, single, cephalic fetus with spontaneous labor), the CD rate was 8.1% in Sweden and 20.4% in BC (rate ratio [RR] for BC versus Sweden = 2.52, 95% confidence interval [CI] 2.49 to 2.56, p < 0.001) and in Group 2 (nullipara, single, cephalic fetus, term gestation with induction of labor or prelabor CD), the rate of CD was 37.3% in Sweden and 45.9% in BC (RR = 1.23, 95% CI 1.22 to 1.25, p < 0.001). The effect of adjustment for maternal characteristics (e.g., age, body mass index), maternal comorbidity (e.g., preeclampsia), fetal characteristics (e.g., head position), and obstetric practice factors (e.g., epidural) ranged from no effect (e.g., among breech deliveries; Groups 6 and 7) to explaining up to 5.2% of the absolute difference in the CD rate (Group 2: adjusted CD rate in BC 40.7%, adjusted RR = 1.09, 95% CI 1.08 to 1.12, p < 0.001). Adjustment also explained a substantial fraction of the temporal change in CD rates among some Robson groups in BC. Limitations of the study include a lack of information on intrapartum details, such as labor duration as well as maternal and perinatal outcomes associated with the observed differences in CD rates. In this study, we found that several factors not included in the Robson classification explain a significant proportion of the spatiotemporal difference in CD rates in some Robson groups. These findings suggest that incorporating these factors into explanatory models using the Robson classification may be useful for ensuring that public health initiatives regarding CD rates are evidence informed.

Vaginal Dinoprostone Insert versus Cervical Ripening Balloon for Term Induction of Labor in Obese Nulliparas-A Randomized Controlled Trial.

Data regarding the preferred induction method in women with obesity is scarce. The current study was aimed at comparing pharmacological and mechanical induction in this population. This prospective randomized controlled trial was conducted between 2016–2020, in nulliparas with a pre-pregnancy body mass index >30. Inclusion criteria were singleton-term pregnancies, bishop score < 5, and indication for induction. Patients were randomized to induction by a cervical ripening balloon (CRB) or a 10 mg vaginal dinoprostone insert. The primary outcome was delivery rate within 24 h. Secondary outcomes included time to delivery, cesarean section rate, maternal and neonatal outcomes, satisfaction, and anxiety. The study population comprised of 83 women in the CRB group and 81 in the dinoprostone group. There was a significant difference in delivery rates within 24 h and time to delivery between the dinoprostone and CRB groups (45% vs. 71%, p = 0.017 and 49.3 ± 6.8 h vs. 23.5 ± 5.9 h, p = 0.003, respectively). There were no differences in cesarean delivery rates or maternal and neonatal outcomes, though CRB induction was associated with a significantly lower rate of tachysystole. Induction with CRB was accompanied by higher satisfaction and lower anxiety. In summary, CRB induction is associated with shorter time to delivery, higher satisfaction, and lower anxiety compared to PGE2 in women with obesity, without compromising maternal or neonatal outcomes.

Maternal education and racial/ethnic disparities in nulliparous, term, singleton, vertex cesarean deliveries in the United States

BACKGROUNDRacial and ethnic disparities in obstetrical and neonatal outcomes are prevalent in the United States. Such racial or ethnic disparities have also been documented in the prevalence of cesarean deliveries.OBJECTIVEWe aimed to evaluate the impact of maternal education on racial or ethnic disparities in the prevalence of low-risk nulliparous, term, singleton, vertex cesarean deliveries in the United States.STUDY DESIGNThis is a retrospective analysis of the Centers for Disease Control and Prevention live births database (2016–2019). Nulliparous, term, singleton, vertex births from the following racial/ethnic groups were included: non-Hispanic White, non-Hispanic Black, non-Hispanic Asian, and Hispanic. Pregnancies complicated by gestational or pregestational diabetes mellitus and hypertensive disorders were excluded. Data were analyzed on the basis of the level of maternal education (less than high school graduate, high school graduate, college graduate, and advanced degree). We compared the prevalence of cesarean deliveries among the different racial or ethnic groups within each education level using Pearson chi-square test with Bonferroni adjustment. Multivariate logistic regression was performed to assess the association between cesarean deliveries and maternal race/ethnicity, maternal education, and the interaction between maternal race or ethnicity and education level, while controlling for potential confounders. To demonstrate the effect of the interaction, separate logistic regression models with similar covariates were performed for each education level and for each race/ethnicity group. Statistical significance was determined as P<.05, and results were displayed as adjusted odds ratios with 95% confidence intervals.RESULTSThe overall prevalence of cesarean deliveries during the study period was 23.4% (695,214 of 2,969,207 births). All racial or ethnic minority groups had higher rates of cesarean deliveries than non-Hispanic White women (non-Hispanic Black, 27.4%; non-Hispanic Asian, 25.6%; Hispanic, 23.0%; and non-Hispanic White, 22.4%; [P<.001 for all comparisons]). Similar racial or ethnic differences in cesarean delivery rates were detected among all education levels. Higher levels of education were associated with a lower likelihood of cesarean delivery (adjusted odds ratio, 0.88; [95% confidence interval, 0.87–0.89]) in women with advanced degrees than in women who did not graduate from high school. However, although maternal education was associated with a protective effect in non-Hispanic White and non-Hispanic Asian women (adjusted odds ratio, 0.83 [95% confidence interval, 0.81–0.85] and adjusted odds ratio, 0.81 [95% confidence interval, 0.77–0.86], respectively, for women with advanced degrees), it had a smaller protective effect in non-Hispanic Black women (adjusted odds ratio, 0.93 [95% confidence interval, 0.89–0.97]) and no protective effect in Hispanic women (adjusted odds ratio, 0.98 [95% confidence interval, 0.96–1.01]).CONCLUSIONWe document a significant racial/ethnic disparity in the prevalence of low-risk nulliparous, term, singleton, vertex cesarean deliveries in the United States. Furthermore, our findings suggest that although a higher level of maternal education is associated with a lower likelihood of cesarean delivery, this protective effect varies among racial or ethnic groups. Further research is needed to investigate the underlying causes for this racial/ethnic disparity.

Racial Disparities in the Rates of and Indications for Cesarean Delivery in California: Are They Changing Over Time?

The aim of this study was to assess whether racial disparities in rates of and indications for cesarean delivery (CD) between non-Hispanic Black and non-Hispanic White birthing people in California changed from 2011 to 2017. This was a retrospective cohort study using a database of birth certificates linked to discharge records. Singleton term live births in nulliparous Black and White birthing people in California between 2011 and 2017 were included. Those with noncephalic presentation, placenta previa, and placenta accreta were excluded. CD rate and indication were obtained from birth certificate variables and International Classification of Diseases codes. Differences in CD rate and indication were calculated for Black versus White individuals using univariable and multivariable logistic regression and adjusted for potential confounders. A total of 348,144 birthing people were included, 46,361 Black and 301,783 White. Overall, 30.9% of Black birthing people underwent CD compared with 25.3% of White (adjusted relative risk [aRR]: 1.2, 95% confidence interval [CI]: 1.2-1.3). From 2011 to 2017, the CD rate fell 11% (26.4-23.7%, p < 0.0001) for White birthing people and 1% for Black birthing people (30.4-30.1%, p = 0.037). Over the study period, Black birthing people had a persistent 1.2- to 1.3-fold higher risk of CD and were persistently more likely to undergo CD for fetal intolerance (aRR: 1.1, 95% CI: 1.1-1.2) and less likely for active phase arrest or arrest of descent (aRRs: 0.9 and 0.4; 95% CIs: 0.9-0.9 and 0.3-0.5). The CD rate decreased substantially for White birthing people and minimally for Black birthing people in our cohort over the study period. Meanwhile, disparities in CD rate and indications between the two groups persisted, despite controlling for confounders. Although care bundles for reducing CD may be effective among White birthing people, they are not associated with reduction in CD rates among Black birthing people nor improvements in racial disparities between Black and White birthing people. Despite increasing attention to racial inequities in obstetric outcomes, there were no changes in disparities in CD rates or indications in California from 2011 to 2017. · Black birthing people are more likely to undergo CD than White despite controlling for confounders.. · There are unexplained differences in CD indication among Black and White birthing people.. · These disparities persisted from 2011 to 2017 despite increasing efforts to decrease CD rates in CA..

Physiological subtypes of gestational glucose intolerance and risk of adverse pregnancy outcomes

Women with gestational glucose intolerance, defined as an abnormal initial gestational diabetes mellitus screening test, are at risk of adverse pregnancy outcomes even if they do not have gestational diabetes mellitus. Previously, we defined the physiological subtypes of gestational diabetes mellitus based on the primary underlying physiology leading to hyperglycemia and found that women with different subtypes had differential risks of adverse outcomes. Physiological subclassification has not yet been applied to women with gestational glucose intolerance. We defined the physiological subtypes of gestational glucose intolerance based on the presence of insulin resistance, insulin deficiency, or mixed pathophysiology and aimed to determine whether these subtypes are at differential risks of adverse outcomes. We hypothesized that women with the insulin-resistant subtype of gestational glucose intolerance would have the greatest risk of adverse pregnancy outcomes. In a hospital-based cohort study, we studied women with gestational glucose intolerance (glucose loading test 1-hour glucose, ≥140 mg/dL; n=236) and normal glucose tolerance (glucose loading test 1-hour glucose, <140 mg/dL; n=1472). We applied homeostasis model assessment to fasting glucose and insulin levels at 16 to 20 weeks' gestation to assess insulin resistance and deficiency and used these measures to classify women with gestational glucose intolerance into subtypes. We compared odds of adverse outcomes (large for gestational age birthweight, neonatal intensive care unit admission, pregnancy-related hypertension, and cesarean delivery) in each subtype to odds in women with normal glucose tolerance using logistic regression with adjustment for age, race and ethnicity, marital status, and body mass index. Of women with gestational glucose intolerance (12% with gestational diabetes mellitus), 115 (49%) had the insulin-resistant subtype, 70 (27%) had the insulin-deficient subtype, 40 (17%) had the mixed pathophysiology subtype, and 11 (5%) were uncategorized. We found increased odds of large for gestational age birthweight (primary outcome) in women with the insulin-resistant subtype compared with women with normal glucose tolerance (odds ratio, 2.35; 95% confidence interval, 1.43-3.88; P=.001; adjusted odds ratio, 1.74; 95% confidence interval, 1.02-3.48; P=.04). The odds of large for gestational age birthweight in women with the insulin-deficient subtype were increased only after adjustment for covariates (odds ratio, 1.69; 95% confidence interval, 0.84-3.38; P=.14; adjusted odds ratio, 2.05; 95% confidence interval, 1.01-4.19; P=.048). Among secondary outcomes, there was a trend toward increased odds of neonatal intensive care unit admission in the insulin-resistant subtype in an unadjusted model (odds ratio, 2.09; 95% confidence interval, 0.99-4.40; P=.05); this finding was driven by an increased risk of neonatal intensive care unit admission in women with the insulin-resistant subtype and a body mass index of <25 kg/m2. Infants of women with other subtypes did not have increased odds of neonatal intensive care unit admission. The odds of pregnancy-related hypertension in women with the insulin-resistant subtype were increased (odds ratio, 2.09; 95% confidence interval, 1.31-3.33; P=.002; adjusted odds ratio, 1.77; 95% confidence interval, 1.07-2.92; P=.03) compared with women with normal glucose tolerance; other subtypes did not have increased odds of pregnancy-related hypertension. There was no difference in cesarean delivery rates in nulliparous women across subtypes. Insulin-resistant gestational glucose intolerance is a high-risk subtype for adverse pregnancy outcomes. Delineating physiological subtypes may provide opportunities for a more personalized approach to gestational glucose intolerance.

Reducing the cesarean delivery rate

BackgroundThe cesarean delivery rate has been rising in recent years, having associated maternal morbidities. Elective induction of labor has also been seen to rise during this same time period. ObjectiveThis current study investigated the difference in the cesarean delivery rate between induction of labor and spontaneous labor among nulliparous, term, singleton, and vertex-presenting women. Study DesignA retrospective cohort in a single institution over a seven-year period was used for this analysis, observing the difference in cesarean delivery rate at different term gestational ages and neonatal morbidity using the 5-minute Apgar score < 5. ResultsA statistically significant difference was found in cesarean delivery rate between those women whose labor was induced and those whose labor began spontaneously, at each term gestational age of labor initiation (P < 0.001). The proportion of indications for induction was described (i.e. elective vs. medically-indicated), and no difference was found for neonatal morbidity between the groups analyzed, using the 5-minute Apgar score as the perinatal outcome measure. ConclusionA comparison was made between spontaneous and induced labor regarding the resultant cesarean delivery rate, and a significant difference was found favoring spontaneous labor. This should be considered when electing to deliver using an induction methodology for nulliparous women, especially when there are no medical indications for it.

Buccal vs vaginal misoprostol combined with Foley catheter for cervical ripening at term (the BEGIN trial): a randomized controlled trial

Combining pharmacologic agents with mechanical ripening achieves the shortest time to labor; however, there is no clear evidence on route of drug administration. Buccal administration of misoprostol has shown greater patient acceptance but remains understudied. This study aimed to evaluate the difference in time to delivery between buccal and vaginal administration of misoprostol along with a Foley catheter for induction of labor. The BEGIN trial (buccal vs vaginal misoprostol combined with Foley catheter for cervical ripening at term) was an institutional review board-approved, randomized clinical trial conducted from June 2019 to January 2020 comparing identical doses (25 μg) of buccal misoprostol and vaginal misoprostol along with a Foley catheter for induction of labor. Randomization was stratified by parity. Labor management was standardized among participants. Individuals undergoing induction of labor at ≥37 weeks with a singleton gestation and needing cervical ripening were included. Our primary outcome was time to delivery. Kruskal-Wallis, Pearson chi-squared, and Cox survival analyses with intent-to-treat principles were performed. A sample size of 216 was planned to detect a 4-hour reduction in delivery time. A total of 215 women (108 in the buccal drug administration group and 107 in the vaginal drug administration group) were randomized. The vaginal route of drug administration achieved a faster median time to delivery than the buccal route of drug administration (19.7 hours in the vaginal route vs 24.1 hours in the buccal route; P<.001). A greater percentage of women in the vaginal drug administration group delivered within 24 hours compared with the buccal drug administration group (65% vs 49%; P=.02). There was no difference in the cesarean delivery rate between the 2 groups (17% in the vaginal drug administration group vs 21% in the buccal drug administration group; P=.6). Individuals who received vaginal misoprostol with Foley catheter delivered 2 times faster than women who received buccal misoprostol with Foley catheter after censoring for cesarean delivery and adjusting for parity (hazard ratio, 2.13; 95% confidence interval, 1.44-3.17). There was no significant difference in maternal and neonatal outcomes. We found that vaginal administration of misoprostol was superior to buccal administration of misoprostol along with a Foley catheter for induction of labor. Furthermore, vaginal administration of misoprostol resulted in twice the chance of delivering earlier compared with buccal administration of misoprostol with no difference in cesarean delivery rates. Therefore, the vaginal route of administration of misoprostol should be preferred among individuals undergoing a combined pharmacologic and mechanical induction.

48 Buccal Versus Vaginal Misoprostol Combined with a Foley Catheter (BEGIN Trial): A Randomized Controlled Trial

Combining pharmacologic agents with mechanical ripening achieves the shortest labor, yet there is no clear evidence on route of drug administration. The use of buccal misoprostol (miso) has shown greater patient acceptance but remains understudied. Our objective was to evaluate the difference in time to delivery of buccal compared to vaginal miso in combination with a Foley catheter (FC) for labor induction (IOL). A randomized clinical trial was conducted from June 2019 through January 2020 comparing identical dosages (25μg) of buccal and vaginal miso in combination with a FC. Randomization was stratified by parity. Labor management was standardized among participants. Women undergoing IOL at ≥37 weeks with a singleton gestation and cervical dilation ≤2cm were included. Our primary outcome was time to delivery. Kruskal-Wallis, Pearson chi-square and Cox survival analyses with intent-to-treat principles were performed. 215 women (108 Buccal, 107 Vaginal) were randomized. Vaginal drug administration achieved a faster median time to delivery compared to buccal miso, (vaginal miso–FC: 19.7hrs vs. buccal miso–FC: 24.1hrs, p< 0.001). A greater percentage of women in the vaginal administration group delivered within 24hrs (65% versus 49%, p=0.02). There was no difference in the cesarean delivery rate between the two groups (vaginal miso–FC: 17% vs. buccal miso–FC: 21%, p=0.6). Women receiving vaginal miso delivered 1.5 times faster than women who received buccal miso after censoring for Cesarean delivery and adjusting for parity, (Hazard Ratio [HR] 1.5, 95% confidence interval [CI] 1.1-2.0). There were no significant differences in maternal and neonatal outcomes. We found that vaginal miso was superior to buccal miso when combined with a FC. Vaginal administration of miso resulted in twice the chance of delivering before a similar dose of buccal miso with no difference in cesarean delivery rates. Therefore, vaginal miso should be the preferred route of drug administration in term IOL.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

44 Six vs. Twelve Hours of Foley Catheter Placement for Induction: A Randomized Controlled Trial

To evaluate whether time to delivery is shorter for women who undergo an induction with cook catheter and oxytocin for six as compared to twelve hours In this randomized controlled trial, labor induction was performed using combination cook catheter and oxytocin. Term women aged 18-50 years old with vertex singletons were included if they were undergoing induction of labor with a Bishop score less than 6 and dilation less than 2cm. Women were randomized to planned removal of the cook catheter at six or twelve hours. Primary outcome was insertion-to-delivery time. We were powered to detect a 4-hour difference with a sample size of 89 women per group (n=178). Planned sensitivity analyses were performed (a) excluding cesarean deliveries and (b) using Cox Proportional Hazards models censoring for cesarean delivery in labor. From February 2019-June 2020 237 women were screened and 178 were randomized 1:1. One person in the twelve-hour group was excluded because her induction was interrupted. Women were similar with regards to baseline characteristics including parity (71% nulliparous in six-hour group and 68% in the twelve-hour group; p=). Insertion-to-delivery time was significantly shorter in the six-hour group (19.2 vs. 24.3 hours, p=0.04) and the proportion of women delivered by 24 hours was significantly greater in the six-hour group (67% vs. 47%, p<0.01). There was no difference in Bishop score at removal. In the Cox Proportional Hazard Model, the six-hour group had a significantly shorter time to delivery (HR 0.67, p=0.02). (Figure 1). There were no differences in cesarean delivery rates (19% vs. 28%, p=0.15) nor any differences in other maternal or neonatal outcomes, including infection rates. Labor induction with a cook catheter and oxytocin with planned removal at 6 hours, rather than 12 hours, results in shorter time to delivery. Decreasing the planned length of time a cook catheter is in place should be considered in clinical protocols.

1148 Racial disparities in cesarean delivery rates: can a machine learning model reduce these biases?

Racial Disparities in Cesarean Delivery Rates: Can a Machine Learning Model Reduce These Biases? Variation exists in both rates of and indication for cesarean delivery (CD) by race which may be due to provider bias. As machine learning (ML) models trained on provider behaviors become more common, it is critical to ensure that these biases are not being replicated and amplified. The objective of this study is to identify whether there are differences in CD rate by race in our total delivery population and whether these persist in a supervised ML model. 39,452 deliveries were performed with this distribution: 21,360 White, 6,976 LatinX, 5,048 Asian, 3,733 Black, and 2,335 Other. Actual rates of CD differed by race: White subjects had the lowest rate (17.8%), Black subjects the highest rate (26.5%), p < 0.001 (Figure 1). As expected, the ML model recommended lower CD rates for all races (Table 1); however, the model recommendations reduced the disparity for some races (White, Black, Other) while exacerbating it for others (Asian, Hispanic). Consistent with the literature, significant variability exists by race in the CD rate. Despite excluding race as a predictor, a ML model trained on low CD rate physicians demonstrated persistent differences in recommendation by race. This suggests that low CD rate physicians also treat patients differently based on race, and consideration should be given to mitigation strategies in creating prescriptive ML models.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

588 There is a wide variation in cesarean delivery rates by the mother’s country of birth

To compare cesarean delivery rates in the United States (US) by mother’s country of birth. Retrospective analysis of the Centers for Disease Control and Prevention, Natality Live Birth database (2016-2018). We calculated cesarean delivery rates (CDR) for nulliparous, term, vertex, singleton (NTSV) pregnancies separately by the country where the mother was born for deliveries that exceeded a total of 2,000 between 2016-2018. The study included a total of 3,212,843 pregnancies from 44 countries with births of 2,000 births or more between 2016-2018. The countries with the highest CDR (Cuba: 45.1% and Iran: 44.1%) had a nearly 3-times increased cesarean delivery rate compared to countries with the lowest rates (Yemen: 16.6% and Moldova: 18.2%). Our study is the first to show significant differences in cesarean delivery rates among countries of mothers’ births. Women born in the 3 countries with the highest rates had a nearly 3-fold increased cesarean delivery rate when compared to women born in countries with the lowest rates. This discrepancy is much higher than discrepancies between the US States (3-fold versus about 1.5-fold). The reasons for these differences are poorly understood. Future attempts to better understand the cause of high cesarean delivery rates require a better understanding of the impact of a woman’s place of birth and race on cesarean delivery rates.

Evidence-based protocol decreases time to vaginal delivery in elective inductions

Labor induction accounts for over 1 in 5 births in the United States. There is large variability in practices of induction of labor. Standardizing aspects of induction of labor has been shown to have beneficial maternal and fetal effects. This study aimed to investigate the impact of the implementation of an evidence-based labor induction protocol on maternal and neonatal outcomes. In February 2018, a contemporary labor induction protocol composed of standardized cervical ripening and early amniotomy was implemented in the labor and delivery unit at a large academic center along with comprehensive training of staff. Maternal and fetal outcomes were compared between patients undergoing induction over a 9 month period following the implementation of the protocol and those undergoing induction 9 months earlier, excluding a 2 week washout period while training occurred. We studied 887 patients who underwent induction of labor of a live singleton at >24 weeks' gestation during our study period (387 patients before the implementation of the protocol and 500 patients after the implementation of the protocol). Baseline characteristics of maternal age, previous vaginal deliveries, and birthweight were similar in patients before and after the implementation of the protocol. There was a significant increase in the number of elective inductions occurring after the implementation of the protocol. There was a significant decrease in time from start of induction to rupture of membranes in all women under the protocol (13.3 hours before the implementation of the protocol vs 10.4 hours after the implementation of the protocol; P≤.001) and decrease in time from start of induction to delivery (21.2 hours before the implementation of the protocol vs 19.7 hours after the implementation of the protocol; P=.04). When the analysis was stratified by elective and nonelective inductions of labor, we found that time from induction of labor initiation to vaginal delivery was shortened after the implementation of the protocol for those undergoing elective induction (18.5 hours vs 14.6 hours; P=.03). There was no difference in cesarean delivery rate (P=.7), chorioamnionitis (P=.3), postpartum hemorrhage (P=.7), or newborn intensive care unit admission (P=.3). The implementation of an evidence-based labor induction protocol was associated with decreased time to delivery, primarily driven by decreased time to vaginal delivery among those undergoing elective inductions of labor, without compromise of maternal or neonatal outcomes.

A Meta-Analysis of Comparing Intermittent Epidural Boluses and Continuous Epidural Infusion for Labor Analgesia.

With the development of medical equipment and techniques in labor anesthesia, it is a major issue to investigate the risks and treatment effects among techniques such as continuous epidural infusion (CEI) and intermittent epidural bolus (IEB). However, there is a controversial result regarding two techniques. This study was conducted through meta-analysis of randomized controlled trials (RCTs) for labor analgesia between the CEI and IEB techniques. The pooled results were presented as weighted mean differences (WMDs) together with 95% confidence intervals (CIs) and odds ratios (ORs) together with 95% CIs, respectively. Eleven RCTs were included in this meta-analysis. Four hundred sixty-five parturients accepted CEI, whereas 473 parturients accepted IEB labor analgesia. Elven identified low- risk bias studies were recruited for meta-analysis. The results presented no statistical difference in cesarean delivery rate between IEB and CEI (OR, 0.96; 95% CI, 0.67–1.37) and duration of second stage of labor (WMD, −3.82 min; 95% CI, −8.28 to 0.64). IEB had statistically significant lessened risk of instrumental delivery (OR, 0.59; 95% CI, 0.39–0.90) and for the use in local anesthetic (WMD, −1.71 mg bupivacaine equivalents per hour; 95% CI, −1.88 and −1.55). Accepted IEB had a higher score of maternal satisfaction (WMD, −6.95 mm; 95% CI, −7.77 to −6.13). Based on evidence, IEB showed a greater benefit for slightly reducing the use in local anesthetic, reduced risk of instrumental delivery, and improved maternal satisfaction for the requirement of labor epidural analgesia for healthy women. In the future, more studies need to be conducted to practice the IEB regimen and explore its influence on labor analgesia.