Persistent Socioeconomic Concentration of Cesarean Delivery in Peru Across Selected Survey-Based Obstetric Marker Strata: A Serial Cross-Sectional Analysis of ENDES Rounds, 2018-2024.

Abstract

Background/Objectives: Cesarean delivery is essential when clinically indicated, but socioeconomic differences in utilization may reflect differences in access, care pathways, preferences, provider practice, or facility characteristics. This study estimated survey-round-specific weighted prevalence of cesarean delivery by household wealth in Peru, quantified socioeconomic inequality, and examined whether the gradient persisted after sequential adjustment and across selected survey-based obstetric marker strata. Methods: We conducted a serial cross-sectional analysis of ENDES (Encuesta Nacional Demográfica y de Salud Familiar) rounds 2018-2024 using each woman's most recent live birth occurring 0-59 months before interview. The official annual REC0111, REC21, and REC41 modules were linked using audited woman- and birth-level keys. Survey-round-specific analyses used original sampling weights; pooled analyses normalized weights within each round so that all seven rounds contributed equally. We estimated Q5-Q1 gaps and ratios, conventional, Wagstaff-normalized, and Erreygers concentration indices, and survey-adjusted Poisson prevalence ratios. A sensitivity analysis was restricted to births in the preceding 12 months. Results: The analytic sample included 127,469 most recent live births. Equal-round weighted cesarean prevalence was 37.31% (95% CI, 36.92-37.70), ranging from 17.67% in Q1 to 61.90% in Q5; the absolute gap was 44.23 percentage points (95% CI, 42.92-45.54) and the ratio was 3.50 (95% CI, 3.38-3.64). The conventional, Wagstaff, and Erreygers indices were 0.228, 0.363, and 0.340, respectively. In the primary conditional model, the Q5-versus-Q1 prevalence ratio was 1.94 (95% CI, 1.84-2.04). The gradient remained in the 12-month sensitivity analysis (PR, 2.07; 95% CI, 1.86-2.30) and across marker strata. Conclusions: Cesarean delivery among recent live births represented in ENDES was consistently concentrated among wealthier women. These findings document socioeconomic inequality in utilization but do not distinguish clinically appropriate use, overuse, or unmet need.