Chapter 21: Cesarean Section/Surgical Management

BACKGROUND

Incidence

Cesarean delivery (CD) is the most common surgery for hospitalized women in the United States. From 1970 to 2014, the rate of primary CD in the United States increased from 5.5% to 32.2%.^1,2 The concurrent rise in rates of overweight and obese women, now representing over two-thirds of the population, is one of myriad factors playing a role in this trend.³ Several studies have reported an association between higher body mass indexes (BMIs) and higher rates of CD.^4,5,6,7,8 In a meta-analysis from 2009, likelihood ratios of undergoing CD were 1.46 (95% confidence interval [CI] 1.34–1.60), 2.05 (95% CI 1.86–2.27), and 2.89 (95% CI 2.28–3.79) in populations of overweight, obese, and severely obese women (BMI > 35–40 depending on the study), respectively, compared with normal-weight pregnant women.⁸ One statewide analysis in the United States determined that 1 in 7 CDs was attributable only to being overweight or obese.⁹

Contributing Factors

While higher rates of preexisting and pregnancy-related diabetes and hypertension are seen in the pregnancies of overweight and obese women, the additional risk for CD appears to be independent of the common comorbidities.⁴ Many factors may play a role in the obese woman’s increased risk for a CD, including, but not limited to, excess weight gain in pregnancy, slower progress in the first stage of labor, differences in myometrial contractility, fetal macrosomia, placental inflammation, inadequate intrapartum fetal monitoring, and soft tissue dystocia.^4,10,11 Iatrogenic causes, such as higher induction rates and provider bias toward CD, may also fuel this trend. The relationship between obesity and CD not only contributes to a rise in health care spending¹² but also affects women’s complications in childbirth, postpartum course, future pregnancy care, and her long-term health and potentially that of her offspring.

Surgical Risk

Surgery on obese patients is associated in general with an increase in operative time, cost, and complications, in particular disturbed wound healing.¹³ CD in obese women is associated with a higher number of complications, such as blood loss, postoperative infection, readmission, and venous thromboembolism (VTE).^11,14,15,16 Importantly for obesity research, the American College of Obstetricians and Gynecologists (ACOG) recognizes severe hypertension, VTE, and obstetric hemorrhage as the three top national priorities for prevention of maternal mortality and morbidity,¹⁷ all more commonly diagnosed in the setting of elevated BMI.

With the global focus on patient safety and utilization of quality benchmarks like readmission and surgical site infection, hospitals are increasingly looking to improve intrapartum and postpartum care for this at-risk population. Recognizing the challenges for the growing population of women with class III or “supermorbid” obesity at delivery, often defined as BMI greater than 50, regional high-risk centers increasingly accept ...