Objective: To investigate whether randomly sampled maternal total cholesterol (TC) and triglycerides (TG) levels during early pregnancy are associated with birth weight (BW) and postnatal growth. Study design: Data were derived from the prospective Amsterdam Born Children and their Development cohort study. Randomly sampled TC and TG levels were determined in early gestation (median, 13; IQR, 12-14 weeks). Outcome measures were BW SDS and weight-for-gestational age; postnatal outcome measures were SDS in weight, length, and body mass index during the first year of life (total n = 2502). Results: The highest TG level was associated with a higher BW SDS (differences 0.20 ± 0.06 between highest and middle quintile; P =.002) and with a higher prevalence (13%) of an infant large for gestational age compared with middle quintile (9%; P =.04). Infants from mothers in the lowest TG quintile had lower SDS in weight, length, and body mass index until age 3 months, and displayed accelerated postnatal growth patterns. Maternal TC was not associated with BW or postnatal growth. Conclusion: High maternal TG levels in the first term of pregnancy were associated with higher BWs and subsequently a higher occurrence of infants large for gestational age, whereas low TG levels were associated with accelerated postnatal growth. Copyright © 2011 Mosby Inc. All rights reserved.