Association between hospital-level cesarean delivery rates and severe maternal morbidity and unexpected newborn complications

Association of Maternal Comorbidity Burden With Cesarean Birth Rate Among Nulliparous, Term, Singleton, Vertex Pregnancies

IMPORTANCE

Cesarean birth rate among nulliparous, term, singleton, vertex (NTSV) pregnancies is a standard quality measure in obstetrical care. There are limited data on how the number and type of preexisting conditions affect mode of delivery among primigravidae, and it is also uncertain how maternal comorbidity burden differs across racial and ethnic groups and whether this helps to explain disparities in the NTSV cesarean birth rate.

OBJECTIVE

To determine the association between obstetric comorbidity index (OB-CMI) score and cesarean delivery among NTSV pregnancies and to evaluate whether disparities in mode of delivery exist based on race and ethnicity group after adjusting for covariate factors.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study of deliveries between January 2019 and December 2021 took place across 7 hospitals within a large academic health system in New York and included all NTSV pregnancies identified in the electronic medical record system. Exclusion criteria were fetal demise and contraindication to labor.

EXPOSURE

The OB-CMI score. Covariate factors assessed included race and ethnicity group (American Indian or Alaska Native, Asian or Pacific Islander, Hispanic, non-Hispanic Black, non-Hispanic White, other or multiracial, and declined or unknown), public health insurance, and preferred language.

MAIN OUTCOME AND MEASURES

Cesarean delivery.

RESULTS

A total of 30 253 patients (mean [SD] age, 29.8 [5.4] years; 100% female) were included. Non-Hispanic White patients constituted the largest race and ethnicity group (43.7%), followed by Hispanic patients (16.2%), Asian or Pacific Islander patients (14.6%), and non-Hispanic Black patients (12.2%). The overall NTSV cesarean birth rate was 28.5% (n = 8632); the rate increased from 22.1% among patients with an OB-CMI score of 0 to greater than 55.0% when OB-CMI scores were 7 or higher. On multivariable mixed-effects logistic regression modeling, there was a statistically significant association between OB-CMI score group and cesarean delivery; each successive OB-CMI score group had an increased risk. Patients with an OB-CMI score of 4 or higher had more than 3 times greater odds of a cesarean birth (adjusted odds ratio, 3.14; 95% CI, 2.90-3.40) than those with an OB-CMI score of 0. Compared with non-Hispanic White patients, nearly all other race and ethnicity groups were at increased risk for cesarean delivery, and non-Hispanic Black patients were at highest risk (adjusted odds ratio, 1.43; 95% CI, 1.31-1.55).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study of patients with NTSV pregnancies, OB-CMI score was positively associated with cesarean birth. Racial and ethnic disparities in this metric were observed. Although differences in the prevalence of preexisting conditions were seen across groups, this did not fully explain variation in cesarean delivery rates, suggesting that unmeasured clinical or nonclinical factors may have influenced the outcome.

Recent trends in term trial of labor after cesarean by number of prior cesarean deliveries

BACKGROUND

Cesarean delivery is a major source of maternal morbidity, and repeat cesarean delivery accounts for 40% of cesarean delivery, but recent data on the trial of labor after cesarean and vaginal birth after cesarean are limited.

OBJECTIVE

This study aimed to report the national rates of trial of labor after cesarean and vaginal birth after cesarean by number of previous cesarean deliveries and examine the effect of demographic and clinical characteristics on these rates.

STUDY DESIGN

This was a population-based cohort study using the US natality data files. The study sample was restricted to 4,135,247 nonanomalous singleton, cephalic deliveries between 37 and 42 weeks of gestation, with a history of previous cesarean delivery and delivered in a hospital between 2010 and 2019. Deliveries were grouped by number of previous cesarean deliveries (1, 2, or ≥3). The trial of labor after cesarean (deliveries with labor among deliveries with previous cesarean delivery) and vaginal birth after cesarean (vaginal deliveries among trial of labor after cesarean) rates were computed for each year. The rates were further subgrouped by history of previous vaginal delivery. Year of delivery, number of previous cesarean deliveries, history of previous cesarean delivery, age, race and ethnicity, maternal education, obesity, diabetes mellitus, hypertension, inadequate prenatal care, Medicaid payer, and gestational age were examined concerning the trial of labor after cesarean and vaginal birth after cesarean using multiple logistic regression. SAS software (version 9.4) was used for all analyses.

RESULTS

The trial of labor after cesarean rates increased from 14.4% in 2010 to 19.6% in 2019 (P<.001). This trend was seen in all categories of number of previous cesarean deliveries. Moreover, vaginal birth after cesarean rates increased from 68.5% in 2010 to 74.3% in 2019. The trial of labor after cesarean and vaginal birth after cesarean rates were the highest for deliveries with a history of both 1 previous cesarean delivery and a vaginal delivery (28.9% and 79.7%, respectively) and the lowest for those with a history of ≥3 previous cesarean deliveries and no history of vaginal delivery (4.5% and 46.9%, respectively). Factors associated with the trial of labor after cesarean and vaginal birth after cesarean rates are similar, but several factors have different directions of effect, such as non-White race and ethnicity, which is associated with a higher likelihood of trial of labor after cesarean but a lower likelihood of successful vaginal birth after cesarean.

CONCLUSION

More than 80% of patients with a history of previous cesarean delivery deliver by repeat scheduled cesarean delivery. With vaginal birth after cesarean rates increasing among those who attempt a trial of labor after cesarean, emphasis should be put on safely increasing the trial of labor after cesarean rates.

Impact of new labor management guidelines on Cesarean rates among low-risk births at New York City hospitals: A controlled interrupted time series analysis

PURPOSE

To examine the impact of the American College of Obstetricians and Gynecologists and Society for Maternal-Fetal Medicine (ACOG-SMFM) 2014 recommendations for preventing unnecessary primary Cesareans.

METHODS

In a population-based cohort of births in New York City from 2012 to 2016, we used controlled interrupted time series analyses to estimate changes in age-standardized Cesarean rates among nulliparous, term, singleton vertex (NTSV) deliveries.

RESULTS

Among 192,405 NTSV births across 40 hospitals, the age-standardized NTSV Cesarean rate decreased after the ACOG-SMFM recommendations from 25.8% to 24.0% (Risk ratio [RR]: 0.93; 95% CI 0.89, 0.97), with no change in the control series. Decreases were observed among non-Hispanic White women (RR: 0.89; 95% CI 0.82, 0.97), but not among non-Hispanic Black women (RR: 0.97; 95% CI 0.88, 1.07), Asian/Pacific Islanders (RR: 1.01; 95% CI 0.91, 1.12), or Hispanic women (RR: 0.94; 95% CI 0.86, 1.02). Similar patterns were observed at teaching hospitals, with no change at nonteaching hospitals.

CONCLUSIONS

While low-risk Cesarean rates may be modifiable through changes in labor management, additional research, and interventions to address Cesarean disparities, are needed.

Pharmacological Interventions in Labor and Delivery

While there is not a wide range of pregnancy-specific drugs, there are some very specific high-risk areas of obstetric care for which unique pharmacological approaches have been established. In preterm birth, labor induction and augmentation, and the management of postpartum hemorrhage, these pharmacological approaches have become the bedrock in managing some of the most common and problematic areas of antenatal and intrapartum care. In this review, we summarize the existing established and emerging evidence that supports and broadens these pharmacological approaches to obstetric management and its impact on clinical practice. It is clear that existing therapeutics are limited. They have largely been developed from our knowledge of the physiology of the myometrium and act on hormonal receptors and their signaling pathways or on ion channels influencing excitability. Newer drugs in development are mostly refinements of these two approaches, but novel agents from plants and improved formulations are also discussed.

Defining a Cesarean Delivery Rate for Optimizing Maternal and Neonatal Outcomes

After the global cesarean delivery rate nearly doubled between 2000 and 2015, cesarean deliveries now account for nearly one third of births in the United States. Although rates have plateaued, the high national cesarean delivery rate has garnered criticism from both lay and academic communities because it has not been associated with improvements in maternal or neonatal outcomes. Efforts are underway to lower the cesarean delivery rate through implementation of hospital-level and national guidelines. However, the cesarean delivery rate that optimizes maternal and neonatal outcomes is not known. Defining a cesarean delivery rate that optimizes perinatal outcomes and reduces morbidity seems simple. However, there are a host of challenges to such a task, including determining the outcomes that are most meaningful to use, deciding the population that should define the rate, and incorporating person-centered decision making, given that people place different value on different outcomes. Rather than a "call" for cesarean delivery rate reductions of a specific and arbitrary magnitude, we need further attention to defining an evidence-based optimal target. This commentary summarizes current national and international cesarean delivery rate targets, discusses the challenges of identifying an evidence-based national cesarean delivery rate target, and explores future considerations for best defining a cesarean delivery rate target.