Objectives- To estimate the proportion of overweight/obesity, associated factors and correlation of leptin, adiponectin, CRP, and IL-6 with BMI, body fat, and visceral fat among women in first trimester Design- Cross-sectional analytical study Setting- Urban and rural primary health care centres, Puducherry, India Population- Pregnant women with singleton pregnancy in the first trimester Methodology- 465 pregnant women were consecutively enrolled. Data were collected on socio-demographic characteristics, obstetric history and maternal anthropometry measurements. Fasting blood glucose, lipid profile & thyroid stimulating hormone were analyzed using Beckman Coulter autoanalyzer and leptin, adiponectin, CRP & IL-6 were analyzed using ELISA kit. Data analysis was done in STATA version 15.1. Outcomes- Proportion of overweight/obesity and factors associated, correlation of serum biomarkers and BMI, body fat, and visceral fat Results- Of the total 465 women, 11.4% (95% CI: 8.6-14.6) were underweight, 28.6% (95% CI: 24.5-32.9) were overweight and 14% (95% CI: 10.9-17.5) were obese. Multivariate log binomial regression indicated that women aged 31-37 years were 1.5 times more likely (aPR = 1.5, 95% CI: 1.1-2.0, p = 0.004) to have BMI ≥ 25 kg/m 2. Energy intake was also found to be significantly associated with overweight/ obesity. Leptin was positively correlated with BMI (r= 0.51, p <0.001), body fat (r= 0.46, p <0.001) and visceral fat (r= 0.40, p <0.001). CRP showed positive correlation with BMI, body fat and visceral fat. Adiponectin was negatively correlated with BMI (r= -0.35, p <0.001), body fat (r= -0.27, p <0.001) and visceral fat (r= -0.32, p <0.001). Conclusion-The study reported high burden of overweight/obesity with advanced maternal age and high energy intake as predictors of high BMI among pregnant women in the first trimester. Leptin and CRP were positively correlated with BMI, body fat and visceral fat.