Objective:To evaluate the association between early pregnancy lipid profiles and pregnancy outcomes.Study Design:Retrospective 6 months analysis of 5218 singleton pregnant women. Each participant's demographic and medical data were collected by questionnaires and medical records. Total cholesterol (TC), triglycerides (TG), high-density lipid cholesterol (HDL-C) and low-density lipid cholesterol (LDL-C) levels were divided into quartiles, and the women were categorized as having low (<25th percentile), referent (25 to <75th percentile) or high (>75th percentile) TC, TG, HDL-C and LDL-C values. Differences between groups were tested using t-test and Pearson's χ 2 -test. Binary logistic regression and multivariate analysis was conducted to evaluate the associations between lipid values and the risk of pregnancy outcomes.Results:(1) Women who subsequently developed adverse pregnancy outcomes had higher levels of TC, TG, LDL-C and lower levels of HDL-C during early pregnancy (<14 gestational weeks). (2) A trend toward an increasing incidence of adverse pregnancy outcomes was noted with increasing levels of TC, TG and LDL-C, and decreasing level of HDL-C. (3) The more numbers of TC, TG and LDL-C above 75th percentile and HDL-C inferior to 25th percentile women had, the higher their risk of developing adverse pregnancy outcomes. (4) Low TG level was a protective factor for gestational diabetes mellitus (GDM) (<1.44 mmol l -1, odds ratio (OR)=0.706, 95% confidence interval (CI), 0.586 to 0.852) and large for gestational age infants (LGA) (<1.44 mmol l -1, OR=0.769, 95% CI, 0.631 to 0.936), and low LDL-C (<1.89 mmol l -1) level was protective factor for preterm birth. High TG (>1.40 mmol l -1, OR=1.327, 95% CI, 1.130 to 1.558), TC (>4.29 mmol l -1, OR=1.250, 95% CI, 1.062 to 1.471), and LDL-C (>2.62 mmol l -1, OR=1.25, 95% CI, 1.069 to 1.480) levels and a low HDL-C (<1.89 mmol l -1, OR=1.190, 95% CI, 1.007 to 1.405) level were associated with increased risk of GDM. A high TG (>1.40 mmol l -1, OR=1.550, 95% CI, 1.025 to 2.343) level was related to high risk of pre-eclampsia (PE), while a high LDL-C (>2.62 mmol l -1, OR=1.400, 95% CI, 1.100 to 1.781) level was risk factor for macrosomia. (5) After adjusting for confounders, early pregnancy TC was an independent risk factor for GDM (ajusted odds ratio OR=1.184, 95% CI, 1.085 to 1.291), TG level was independently associated with the prevalence of GDM (aOR=1.253, 95% CI, 1.141 to 1.375) and PE (aOR=1.245, 95% CI, 1.023 to 1.516), and LDL-C level was significantly associated with risk of GDM (aOR=1.162, 95% CI, 1.052 to 1.283) and preterm birth (aOR=1.264, 95% CI, 1.065, 1.501).Conclusions:Early pregnancy high levels of TC, TG, LDL-C and low level of HDL-C may be predictive biomarkers for adverse pregnancy outcomes, while early pregnancy low TC, TG, LDL-C levels and high HDL-C levels could have some protective roles.