Undiagnosed hypertension among pregnant women in Peru: prevalence, inequities, and geographic variability. Analysis of the demographic and family health survey.

OBJECTIVE: To estimate the prevalence of undiagnosed hypertension among pregnant women in Peru, assess socioeconomic inequities, and characterize departmental geographic variability during 2014-2024. METHODS: We conducted an analytical cross-sectional study using the Demographic and Family Health Survey (ENDES) 2014-2024. The sample included 5243 pregnant women aged 15-49 years with valid blood pressure measurements and no prior hypertension diagnosis. Undiagnosed hypertension was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg among women without self-reported diagnosis. Weighted prevalences and 95% confidence intervals (95% CI) were estimated. Socioeconomic inequities were assessed using the Slope Index of Inequality (SII), Relative Index of Inequality (RII), and Erreygers concentration index. Spatial autocorrelation was assessed using Moran's I. RESULTS: The prevalence of undiagnosed hypertension was 5.6% (95% CI: 4.4-6.7). Prevalence was higher in urban than rural areas (6.1% vs 4.2%) and in the richest versus poorest quintile (6.4% vs 3.8%), although these contrasts were imprecise. The SII was 3.36 percentage points (95% CI: -0.72 to 7.44), the RII was 1.83 (95% CI: 0.92-3.64), and the Erreygers index was 0.021 (95% CI: 0.007-0.035; p = 0.003), indicating a small pro-rich concentration. Moran's I was positive and statistically significant after correction to 25 ENDES spatial units (I = 0.294; p = 0.013). CONCLUSIONS: Undiagnosed hypertension affected approximately one in eighteen pregnant women in Peru. Findings suggest modest pro-rich concentration and significant departmental spatial autocorrelation.