Background: Early-life growth is associated with individual cardiometabolic risk factors, but its relationship with overall cardiovascular health (CVH) in low- and middle-income countries (LMICs) is unclear. We examined associations of maternal, household, and child growth factors with young-adult CVH across four LMIC birth cohorts. Methods: We analyzed harmonized data from the Consortium of Health-Oriented Research in Transitioning Societies (COHORTS), including 4,582 participants ages 18-30 years from Brazil, Guatemala, the Philippines, and South Africa. CHV was assessed using a modified American Heart Association Life's Simple 7 score based on body mass index (BMI), blood pressure (BP), fasting blood glucose (FBG), and smoking. Site-specific multivariable ordinal logistic regression models evaluated associations between early-life factors and CVH. Results: Men had poorer CVH than women across most sites, largely because of less favorable BP and smoking profiles. Higher birthweight was associated with lower odds of better CVH in Brazil (AOR=0.81; 95% CI: 0.71-0.94) and the Philippines (AOR=0.63; 95% CI: 0.45-0.87). Greater conditional relative weight at 2 years was also inversely associated with CVH in both sites. Birthweight, conditional height and conditional relative weight at 2 years were strongly associated with adult BMI, whereas associations with BP and FBG were weaker. Attained schooling was associated with CVH in Brazil (AOR = 1.13 per year; 95% CI: 1.10-1.16), and the Philippines (AOR = 1.17; 95% CI: 1.10-1.24). Conclusions: Early-life growth patterns and educational attainment are associated with cardiovascular health in young adulthood across diverse LMIC settings, supporting life-course strategies to promote cardiovascular health.