Objective: Indo-Asians have one of the highest rates of cardiovascular disease worldwide. Estimates and determinants of left ventricular hypertrophy (LVH) in this population are not known. We sought to determine the prevalence of and risk factors for LVH in Karachi, Pakistan.Methods: We conducted a population-based cross-sectional study on 320 randomly selected adults from the general population aged 40 years or above. LVH was defined as increased left ventricular mass index (LVMI) on echocardiogram (>115 g/m2 in men and >95 g/m2 in women) employing the adjusted Devereux equation. Multivariable models were built and logistic regression analysis was done for the primary outcome of LVH.Results: Mean age of subjects was 52.7 (10.4) years, 50% were women. Mean LVMI (SD) was 72.0 (19.2) [median 71.1] g/m2 in men and 75.7 (25.9) [median 72.9] g/m2 in women. The overall prevalence of LVH was 21.9% in women and 2.5% in men (P < 0.001). The factors (odds ratio, 95% CI) independently associated with LVH were women versus men (11.35, 3.79–34.02), systolic blood pressure > versus < 140 mmHg (2.70, 1.23–5.93), waist circumference (1.05, 1.02–1.08 for each cm increase) and illiteracy (2.43, 1.07–5.52).Conclusions: Urban Pakistani women appear to have a disproportionately high risk of LVH compared to men using standard echocardiographic criteria. Further research is needed to verify these results by establishing population-specific reference values for LVH and correlating cut-points for increased LVMI with prognosis. Concerted efforts are needed to reduce the high burden of risk factors in Indo-Asian women.