What Is the Ideal Cesarean Rate?

For many years, discussions around the “ideal cesarean rate” tended to refer to a 1985 World Health Organization (WHO) consensus statement that recommended a population-based cesarean rate between 10% to 15% to optimize maternal and infant health outcomes. Last week, a study was published in JAMA that used data from all WHO member countries and found an inverse association between cesarean rates and maternal and infant mortality for cesarean rates up to 19%. That is, on average, higher cesarean rates were associated with lower maternal and infant mortality until cesarean rates reached 19%, after which point higher cesarean rates were not associated with lower maternal and infant mortality rates. The strongest association was seen in countries with cesarean rates up to 7%, and a more modest association characterized countries with cesarean rates between 8% and 19%.

So, Is 19% the New “Ideal”?

This new study does add important new information to the ongoing discussion on appropriate use of cesarean delivery and efforts to lower US cesarean rates to more closely align with international standards. The desire to use evidence to inform population health goals for cesarean use is commendable, but it’s very important to understand the nuances and caveats of the data presented in the JAMA study. First and foremost, in a cross-sectional, associational analysis, it is crucial to remember that correlation does not equal causation. The authors of the JAMA study, recognizing the limitations of their ecological study design, urge caution. In an excellent story about this paper published in Wired, study co-author Alex Haynes, MD, MPH says, “I wouldn’t want to make a direct recommendation for what the C-section rate should be from these data.” This is wise.

The practical question of the “ideal” cesarean rate has to do with ensuring that all patients who need a cesarean have one, and all patients who do not need a cesarean can successfully give birth vaginally. This is a question of patient-provider communication, clinical management, and healthcare delivery at the systems level. And these questions are actually better addressed by other papers published in the same issue of JAMA. For example, in the accompanying opinion article, Mary D’Alton, MD, and Mary Hehir, MD, highlight the importance of optimizing clinical practice patterns to conform to emerging standards of evidence-based care in obstetrics. In addition, another original research contribution in this same issue highlights the long-term effects on children of planned cesarean vs vaginal delivery. While this observational study design also has limitations, the longitudinal nature of the study and the presence of a comparison group produce evidence that can help inform discussions about benefits and harms in delivery mode decisions.

The Role of Health Plans and Delivery Systems

Beyond the role that clinicians themselves play in care management and communication of risks and benefits, there is an important role for payers and healthcare delivery systems in supporting clinicians in providing evidence-based maternity care. Currently, we witness substantial variability across institutions in cesarean rates, maternal morbidity, and costs of childbirth care. This variability indicates potential for improvement in clinical management, and in patient-provider communication, to ensure more appropriate use of cesarean procedures on an individual basis. As guidelines are more consistently adopted across institutions and clinicians, it’s likely that population-level cesarean rates in the United States may decline, and even approach levels that are optimally associated with maternal and neonatal outcomes. But the way forward is not to aim for a cesarean rate of 19%, but rather to align policies and systems with evidence.

There are concrete steps that health plans and healthcare delivery systems can take to support appropriate use of cesarean. Hospital and health plan administrators should closely monitor quality metrics within the systems that they oversee. Research shows that hospitals with boards that use clinical quality metrics more effectively also have higher performance on these metrics. Deciding on quality metrics for maternity care, however, is a challenge. While this field is evolving, recent research by Elizabeth Howell, MD, MPP, and colleagues has shown that commonly-used hospital quality metrics have not been associated with reduced maternal morbidity and mortality. To improve measurement and quality related to cesarean use, hospitals and health plans may want to consider adoption of a newly-proposed measure of low-risk cesarean rates that has been vetted and endorsed by the Society for Maternal Fetal Medicine.

There is reason for excitement as emerging data help to inform ongoing efforts on the part of patients, clinicians, payers, employers, hospitals, and other stakeholders who care deeply about ensuring that cesarean delivery is used appropriately for every birth.