Objective To investigate the association between the maternal lipid profile in early pregnancy and embryonic growth. Design Prospective population-based cohort study. Setting Rotterdam, the Netherlands. Population We included 1474 women from the Generation R(otterdam) Study. Methods The maternal lipid profile was defined as total cholesterol, triglycerides (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), remnant cholesterol, non-high-density (non-HDL-c) lipoprotein cholesterol concentrations and the triglycerides/high-density lipoprotein (TG/HDL-c) ratio. Additionally, maternal glucose concentrations were assessed. Associations were studied with linear regression models, adjusted for confounding factors: maternal age, pre-pregnancy BMI, parity, educational level, ethnicity, smoking and folic acid supplement use Main Outcome Measures Crown-rump length (CRL). Results Triglycerides and remnant cholesterol concentrations are positively associated with embryonic growth (fully adjusted models, 0.17 SDS: 95% CI 0.03 ; 0.30, and 0.17 SDS: 95% CI 0.04 ; 0.31, respectively). These associations were not present in women with normal weight (triglycerides and remnant cholesterol: fully adjusted model, 0.44 SDS: 95% CI 0.15 ; 0.72). Associations between maternal lipid concentrations and embryonic growth were not attenuated after adjustment for glucose concentrations. Total cholesterol, HDL-c, LDL-c, non-HDL-c concentrations and the TG/HDL-c ratio were not associated with embryonic growth. Conclusions Higher triglycerides and remnant cholesterol concentrations in early pregnancy are associated with increased embryonic growth, most notably in overweight women. Keywords Pregnancy, Cholesterol, Low-density lipoprotein (LDL-c), High-density lipoprotein (HDL-c), Triglycerides, Intrauterine development, Fetal growth, Early pregnancy Tweetable abstract The maternal lipid profile in pregnancy is associated with embryonic growth.